fmea handbook
TRANSCRIPT
Front Cover
The content of this document is the technical equivalent of SAE J-1739.Potential Failure Mode and Effects Analysis (FMEA) should be used bysuppliers to companies subscribing to QS-9000 or equivalent document.
POTENTIALFAILURE MODE ANDEFFECTS ANALYSIS
(FMEA)
REFERENCE MANUAL
First Edition Issued February, 1993 • Second Edition, February, 1995 • Third Edition, April, 2001 Copyright © 1993, © 1995, © 2001
DaimlerChrysler Corporation, Ford Motor Company, General Motors Corporation
FOREWORD1st and 2nd Edition
This reference Manual and Reporting Format was developed by the Failure Mode and Effects Analysis(FMEA) teams at Chrysler, Ford and General Motors, working under the auspices of the AutomotiveDivision of the American Society for Quality Control (ASQC) and the Automotive Industry Action Group(AIAG).
The ASQC/AIAG Task Force charter is to standardize the reference manuals, procedures, reporting formatsand technical nomenclature used by Chrysler, Ford, and General Motors in their respective supplier qualitysystems. Accordingly, this manual and format, which is approved and endorsed by Chrysler, Ford andGeneral Motors, should be used by suppliers implementing FMEA techniques into their design/manufacturing processes.
In the past, Chrysler, Ford and General Motors each had their own guidelines and formats for insuringsupplier FMEA compliance. Differences between these guidelines and formats resulted in additionaldemands on supplier resources. To improve upon this situation, Chrysler, Ford and General Motors agreedto develop, and, through AIAG, distribute this Manual. The work group responsible for the Manual was ledbe George Baumgartner of Ford Motor Company.
This Manual provides general guidelines for preparing an FMEA. It does not give specific instructions onhow to arrive at each FMEA entry, a task best left to each FMEA team. This Manual also is not intended tobe a comprehensive FMEA reference source or training document.
While these guidelines are intended to cover all situation normally occurring either in the design phase orprocess analysis, there will be questions that arise. These questions should be directed to your customer'sSupplier Quality Assurance (SQA) activity. If you are uncertain as to how to contact the appropriate SQAactivity, the buyer in your customer's Purchasing office can help.
The Task Force gratefully acknowledges: the leadership and commitment of Vice Presidents Thomas T.Stallkamp at Chrysler, Norman F. Ehlers at Ford, and J. Ignasio Lopez de Arriortua of General Motors; theassistance of the AIAG in the development, production, and distribution of the Procedure; the guidance ofTask Force principals Russ Jacobs (Chrysler), Steve Walsh (Ford), Dan Reid (General Motors), and RadSmith; and the assistance of the ASQC Automotive Division Reading Team. This team, led by Tripp Martin(Peterson Spring), reviewed the Manual for technical content and accuracy and made valuablecontributions to form and content. Since the Manual was developed to meet specific needs of theautomotive industry, the ASQC voluntary standards process defined by ASQC policies and procedures wasnot used in its development.
Additional copies can be ordered from AIAG and/or permission to copy portions of this Procedure for usewithin supplier organizations should be obtained from AIAG at 248-358-3003.
FOREWORD3rd Edition
The FMEA 3rd Edition (QS-9000) is a reference manual to be used by suppliers to DaimlerChrysler, FordMotor Company, and General Motors Corporation as a guide to assist them in the development of bothDesign and Process FMEAs. This reference manual is intended to clarify questions concerning the techni-cal development of FMEAs.
This reference manual is consistent with the Supplier Quality Requirements Task Force charter to standard-ize the reference manuals, procedures, reporting formats and technical nomenclature used by suppliers toDaimlerChrysler, Ford Motor Company, and General Motors Corporation. Accordingly the FMEA, 3rdEdition Manual is written to provide guidance for the supplier. The manual does not define requirements, itdoes provide general guidelines intended to cover situations normally occurring when preparing FMEAsduring the design phase or process analysis phase.
This manual is the technical equivalent of SAE J1739, for Design and Process FMEAs. However, it doesnot include an application for Machinery FMEA. Interested parties in Machinery FMEA may refer to SAEJ1739 for a related example.
The Supplier Quality Requirements Task Force would like to thank the following individuals, and theircompanies, who have contributed their time and efforts to the development of either this edition of theFMEA manual or earlier editions.
3rd EditionKevin A. Lange - DaimlerChryslerSteven C. Leggett - General Motors CorporationBeth Baker - AIAG
Earlier EditionsHoward Riley - DaimlerChrysler Mark T. Wrobbel - DaimlerChryslerGeorge R. Baumgartner - Ford Motor Company Rebecca French - General MotorsLawrence R. McCullen - General Motors Mary Ann Raymond - BoschRobert A. May - Goodyear William Ireland - Kelsey-HayesTripp Martin - Peterson Spring
In addition, the Supplier Quality Requirements Task Force would like to thank the following individuals fromthe SAE J1739 work group who contributed significantly to the technical changes and improvements in thisedition.
William D. Carlson - DaimlerChryslerGlen R. Vallance - Ford Motor CompanyCarl S. Carlson - General Motors Corporation
This manual is a copyright of DaimlerChrysler, Ford Motor Company and General Motors Corporation, withall rights reserved. Additional copies may be obtained from AIAG, Southfield, Michigan, by calling 248-358-3003. Supply chain organizations of DaimlerChrysler, Ford Motor Company or General Motors Corporationhave permission to copy forms used in this manual.
TABLE OF CONTENTS
Page Number
General Information ................................................................................................................................... 1
Overview ......................................................................................................................................... 1What Is an FMEA ............................................................................................................................ 1Manual Format ................................................................................................................................ 1FMEA Implementation .................................................................................................................... 2
Design FMEA .............................................................................................................................................. 7
Introduction ................................................................................................................................................... 9
Customer Defined ........................................................................................................................... 9Team Effort ..................................................................................................................................... 9
Development of a Design FMEA ............................................................................................................... 10
1) FMEA Number ........................................................................................................................ 13 2) System, Subsystem, or Component Name and Number ....................................................... 13 3) Design Responsibility ............................................................................................................. 13 4) Prepared By ............................................................................................................................ 13 5) Model Year(s)/Program(s) ...................................................................................................... 13 6) Key Date ................................................................................................................................. 13 7) FMEA Date ............................................................................................................................. 13 8) Core Team .............................................................................................................................. 15 9) Item/Function .......................................................................................................................... 15
10) Potential Failure Mode ........................................................................................................... 1511) Potential Effect(s) of Failure ................................................................................................... 1712) Severity (S) ............................................................................................................................. 17
Suggested Evaluation Criteria ................................................................................................ 1913) Classification .......................................................................................................................... 1914) Potential Cause(s)/Mechanism(s) of Failure .......................................................................... 1915) Occurrence (O) ....................................................................................................................... 21
Suggested Evaluation Criteria ................................................................................................ 2316) Current Design Controls ......................................................................................................... 2517) Detection (D) .......................................................................................................................... 25
Suggested Evaluation Criteria ................................................................................................ 2718) Risk Priority Number (RPN) ................................................................................................... 2719) Recommended Action(s) ........................................................................................................ 2920) Responsibility for the Recommended Action(s) ..................................................................... 2921) Action(s) Taken ...................................................................................................................... 3122) Action Results ......................................................................................................................... 31
Follow-Up Actions ...................................................................................................................................... 31
Process FMEA .......................................................................................................................................... 33
Introduction ................................................................................................................................................ 35
Customer Defined ......................................................................................................................... 35Team Effort ................................................................................................................................... 35
– I –
TABLE OF CONTENTS - continued
Page Number
Development of a Process FMEA ............................................................................................................. 37
1) FMEA Number ......................................................................................................................... 37 2) Item ......................................................................................................................................... 39 3) Process Responsibility ............................................................................................................ 39 4) Prepared By ............................................................................................................................ 39 5) Model Year(s)/Program(s) ...................................................................................................... 39 6) Key Date .................................................................................................................................. 39 7) FMEA Date .............................................................................................................................. 39 8) Core Team .............................................................................................................................. 39 9) Process Function/Requirements ............................................................................................. 3910) Potential Failure Mode ............................................................................................................ 3911) Potential Effect(s) of Failure .................................................................................................... 4112) Severity (S) .............................................................................................................................. 41
Suggested Evaluation Criteria ................................................................................................ 4313) Classification ........................................................................................................................... 4514) Potential Cause(s)/Mechanism(s) of Failure ........................................................................... 4515) Occurrence (O) ....................................................................................................................... 47
Suggested Evaluation Criteria ................................................................................................ 4716) Current Process Controls ........................................................................................................ 4917) Detection (D) ........................................................................................................................... 51
Suggested Evaluation Criteria ................................................................................................ 5318) Risk Priority Number (RPN) .................................................................................................... 5319) Recommended Action(s) ......................................................................................................... 5520) Responsibility for the Recommended Action(s) ...................................................................... 5721) Action(s) Taken ....................................................................................................................... 5722) Action Results .......................................................................................................................... 57
Follow-Up Actions ...................................................................................................................................... 57
APPENDICES
A Design FMEA Quality Objectives ............................................................................................ 59B Process FMEA Quality Objectives ........................................................................................... 60C Design FMEA Block Diagram Example ................................................................................... 61D Standard Forms for Design FMEA (1 and 2 column for controls) ........................................... 62E Design FMEA Example ............................................................................................................ 64F System FMEA .......................................................................................................................... 65G Standard Forms for Process FMEA (1 and 2 column for controls) .......................................... 68H Process FMEA Example .......................................................................................................... 70I Occurrence Evaluation Criteria With Cpk Values .................................................................... 71
– Il –
– Ill –
– 1 –
Overview This manual introduces the topic of Potential Failure Mode andEffects Analysis (FMEA) and gives general guidance in theapplication of the technique.
What Is an FMEA An FMEA can be described as a systematic group of activitiesintended to: (a) recognize and evaluate the potential failure of aproduct/process and the effects of that failure, (b) identifyactions that could eliminate or reduce the chance of thepotential failure occurring, and (c) document the entire process.It is complementary to the process of defining what a design orprocess must do to satisfy the customer.
All FMEAs focus on the design, whether it be of the product, orprocess.
Manual Format This reference document presents two types of FMEA: DesignFMEA, and Process FMEA.
This manual should be used by suppliers that subscribe to QS-9000 or its equivalent. FMEA teams are allowed to use theguidelines listed herein in the manner that will be most effectivefor a given situation.
GENERAL INFORMATION
– 2 –
FMEA Implementation Because of the general industry trend to continually improveproducts and processes whenever possible, using the FMEA asa disciplined technique to identify and help minimize potentialconcern is as important as ever. Studies of vehicle campaignshave shown that fully implemented FMEA programs could haveprevented many of the campaigns.
One of the most important factors for the successfulimplementation of an FMEA program is timeliness. It is meant tobe a “before-the-event” action, not an “after-the-fact” exercise.To achieve the greatest value, the FMEA must be done before aproduct or process failure mode has been incorporated into aproduct or process. Up-front time spent properly completing anFMEA, when product/process changes can be most easily andinexpensively implemented, will minimize late change crises. AnFMEA can reduce or eliminate the chance of implementing apreventive/corrective change that would create an even largerconcern. Communication and coordination should occuramong all FMEA teams.
Figure 1 depicts the sequence in which an FMEA should beperformed. It is not simply a case of filling out the form butrather of understanding the FMEA process in order to eliminaterisk and plan the appropriate controls to ensure customersatisfaction.
There are three basic cases for which FMEA's are generated,each with a different scope or focus:
Case 1: New designs, new technology, or new process. Thescope of the FMEA is the complete design,technology, or process.
Case 2: Modifications to existing design or process (assumesthere is a FMEA for the existing design or process).The scope of the FMEA should focus on themodification to design process, possible interactionsdue to the modification, and field history.
Case 3: Use of existing design or process in a newenvironment, location, or application (assumes thereis an FMEA for the existing design or process). Thescope of the FMEA is the impact of the newenvironment or location on the existing design orprocess.
Although responsibility for the preparation of the FMEA isusually assigned to an individual, FMEA input should be a teameffort. A team of knowledgeable individuals should beassembled (e.g., engineers with expertise in design, analysis/testing, manufacturing, assembly, service, recycling, quality,and reliability). The FMEA is initiated by the engineer from theresponsible activity, which can be the Original EquipmentManufacturer (i.e., produces the final product), a supplier, or asubcontractor.
– 3 –
Figure 1. FMEA Process Sequence
Pot
entia
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ailu
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ode
Pot
entia
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ffect
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ailu
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Res
ults
Act
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Tak
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pons
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ty&
Tar
get
Com
plet
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Dat
e
Cur
rent
Con
trol
s
Pot
entia
lC
ause
(s)/
Mec
hani
sm(s
)of
Fai
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Sub
syst
em F
unct
ion
Req
t's
Rec
omm
ende
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How
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How
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pp
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– 4 –
It is not appropriate to compare the ratings of one team’s FMEAwith the ratings of another team’s FMEA, even if the product/process appears to be identical, since each team's environmentis unique and thus the respective individual ratings will beunique (i.e., the ratings are subjective).
A review of the FMEA document against FMEA qualityobjectives (see Appendix A and Appendix B) is recommended,including a management review.
Follow-Up The need for taking effective preventive/corrective actions, withappropriate follow-up on those actions, cannot beoveremphasized. Actions should be communicated to allaffected activities. A thoroughly thought-out and well-developedFMEA will be of limited value without positive and effectivepreventive/corrective actions.
The responsible engineer is in charge of ensuring that allrecommended actions have been implemented or adequatelyaddressed. The FMEA is a living document and should alwaysreflect the latest level, as well as the latest relevant actions,including those occurring after the start of production.
The responsible engineer has several means of assuring thatrecommended actions are implemented. They include, but arenot limited to the following:
a. Reviewing designs, processes, and, drawings, to ensure thatrecommended actions have been implemented.
b. Confirming the incorporation of changes to design/assembly/manufacturing documentation.
c. Reviewing Design/Process FMEAs, special FMEAapplications, and Control Plans.
– 5 –
– 6 –
POTENTIAL
FAILURE MODE AND EFFECTS ANALYSIS
IN
DESIGN
(DESIGN FMEA)
DESIGN FMEA
– 7 –
– 8 –
– 9 –
A Design Potential FMEA is an analytical technique usedprimarily by a Design-Responsible Engineer/Team as a meansto ensure that, to the extent possible, potential failure modesand their associated causes/mechanisms have been consideredand addressed. End items, along with every related system,subassembly, and component, should be evaluated. In its mostrigorous form, an FMEA is a summary of the team’s thoughts(including an analysis of items that could go wrong based onexperience) as a component, subsystem, or system is designed.This systematic approach parallels, formalizes, and documentsthe mental disciplines that an engineer normally goes through inany design process.
The Design Potential FMEA supports the design process inreducing the risk of failures (including unintended outcomes) by:
• Aiding in the objective evaluation of design, includingfunctional requirements and design alternatives,
• Evaluating the initial design for manufacturing,assembly, service, and recycling requirements,
• Increasing the probability that potential failure modesand their effects on system and vehicle operation havebeen considered in the design/development process,
• Providing additional information to aid in the planning ofthorough and efficient design, development, andvalidation programs,
• Developing a ranked list of potential failure modesaccording to their effect on the “customer,” thusestablishing a priority system for design improvements,development, and validation testing/analysis,
• Providing an open issue format for recommending andtracking risk-reducing actions, and,
• Providing future reference, e.g., lessons learned, to aidin analyzing field concerns, evaluating design changes,and developing advanced designs.
Customer Defined The definition of “Customer” for a Design FMEA is not only the“End User” but also the design-responsible engineers/teams ofthe vehicle or higher-level assemblies, and/or themanufacturing/process-responsible engineers in activities suchas manufacturing, assembly, and service.
Team Effort During the initial Design FMEA process, the responsibleengineer is expected to directly and actively involverepresentatives from all affected areas. These areas of expertiseand responsibility should include but are not limited toassembly, manufacturing, design, analysis/test, reliability,materials, quality, service, and suppliers, as well as the designarea responsible for the next higher or lower assembly orsystem, sub-assembly, or component. The FMEA should be acatalyst to stimulate the interchange of ideas between thefunctions affected and thus promote a team approach.
INTRODUCTION
DESIGN FMEA
Unless the responsible engineer is experienced with FMEA andteam facilitation, it is helpful to have an experienced FMEAfacilitator assist the team in its activities.
The Design FMEA is a living document and should:• Be initiated before or at design concept finalization,• Be continually updated as changes occur or additional
information is obtained throughout the phases ofproduct development, and
• Be fundamentally completed before the productiondrawings are released for tooling.
Considering that manufacturing/assembly needs have beenincorporated, the Design FMEA addresses the design intent andassumes the design will be manufactured/assembled to thisintent. Potential failure modes and/or causes/mechanisms thatcan occur during the manufacturing or assembly process neednot but may be included in a Design FMEA. When not included,their identification, effect, and control are covered by theProcess FMEA.
The Design FMEA does not rely on process controls toovercome potential design weaknesses, but it does take thetechnical/physical limits of a manufacturing/assembly processinto consideration, for example:
• Necessary mold drafts• Limited surface finish• Assembling space/access for tooling• Limited hardenability of steels• Tolerances/process capability/performance
The Design FMEA can also take into consideration thetechnical/physical limits of product maintenance (service) andrecycling, for example:
• Tool access• Diagnostic capability• Material classification symbols (for recycling)
DEVELOPMENT OF A DESIGN FMEAThe design-responsible engineer has at his or her disposal anumber of documents that will be useful in preparing the DesignFMEA. The process begins by developing a listing of what thedesign is expected to do and what it is expected not to do, i.e.,the design intent. Customer wants and needs — as may bedetermined from sources such as Quality Function Deployment(QFD), Vehicle Requirements Documents, known productrequirements, and/or manufacturing/assembly/service/recyclingrequirements — should be incorporated. The better thedefinition of the desired characteristics, the easier it is to identifypotential failure modes for preventive/corrective action.
A Design FMEA should begin with a block diagram for thesystem, subsystem, and/or component being analyzed.
– 10 –
DESIGN FMEA
– 11 –
An example block diagram is shown in Appendix C. The blockdiagram can also indicate the flow of information, energy, force,fluid, etc. The object is to understand the deliverables (input) tothe block, the process (function) performed in the block, and thedeliverables (output) from the block.
The diagram illustrates the primary relationship among the itemscovered in the analysis and establishes a logical order to theanalysis. Copies of the diagrams used in FMEA preparationshould accompany the FMEA.
In order to facilitate documentation of the analysis of potentialfailures and their consequences, a blank Design FMEA form isavailable in Appendix D.
DESIGN FMEA
– 12 –
TABLE 1. DESIGN FMEA
Item
Fun
ctio
n
Fro
nt D
oor
L.H
.H
8HX
-000
0-A
• In
gres
s to
and
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upan
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nd
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impa
ct
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uppo
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anch
orag
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r
door
har
dwar
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incl
udin
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mirr
or,
hi
nges
, lat
ch
and
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dow
re
gula
tor
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rovi
de p
rope
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surf
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for
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pear
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ite
ms
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• U
nsat
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due
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t thr
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Impa
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o
f int
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or
har
dwar
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C l a s s
S e v 7 7 7 7 7
O c c u r 6 4 2 5 4
D e t e c 7 7 2 8 4
R.
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N.
294
196
28 280
112
S e v 7 7 7 7
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P.
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O c c 2 2 1 1
D e t 2 2 3 1
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16 SA
MP
LE
– 13 –
1) FMEA Number Enter the FMEA document number, which may be used fortracking.
Note: For an example of items 1-22 see Table 1.
Indicate the appropriate level of analysis and enter the nameand number of the system, subsystem, or component beinganalyzed. The FMEA team members must decide on whatconstitutes a system, subsystem, or component for theirspecific activities. The actual boundaries that divide a system,subsystem, and component are arbitrary and must be set by theFMEA team. Some descriptions are provided below and someexamples are provided in Appendix F.
System FMEA ScopeA system can be considered to be made up of varioussubsystems. These subsystems often have been designed bydifferent teams. Some typical System FMEAs might cover thefollowing systems: Chassis System, or Powertrain System, orInterior System, etc. Thus, the focus of the System FMEA is toensure that all interfaces and interactions are covered amongthe various subsystems that make up the system as well asinterfaces to other vehicle systems and the customer.
Subsystem FMEA ScopeA Subsystem FMEA is generally a sub-set of a larger system.For example, the front suspension subsystem is a sub-set of thechassis system. Thus, the focus of the Subsystem FMEA is toensure that all interfaces and interactions are covered amongthe various components that make up the subsystem.
Component FMEA ScopeA Component FMEA is a generally an FMEA focused on thesub-set of a subsystem. For example, a strut is a component ofthe front suspension (which is a subsystem of the chassissystem.)
3) Design Responsibility Enter the OEM, department, and group. Also include thesupplier name, if applicable.
4) Prepared By Enter the name, telephone number, and company of theengineer responsible for preparing the FMEA.
5) Model Year(s)/Program(s) Enter the intended model year(s)/program(s) that will use and/orbe affected by the design being analyzed (if known).
6) Key Date Enter the initial FMEA due date, which should not exceed thescheduled production design release date.
7) FMEA Date Enter the date the original FMEA was compiled and the latestrevision date.
DESIGN FMEA
2) System,Subsystem, orComponent Nameand Number
– 14 –
TABLE 1. DESIGN FMEA
Item
Fun
ctio
n
Fro
nt D
oor
L.H
.H
8HX
-000
0-A
• In
gres
s to
and
eg
ress
from
ve
hicl
e•
Occ
upan
t
prot
ectio
n
from
wea
ther
,
nois
e, a
nd
side
impa
ct
• S
uppo
rt
anch
orag
e fo
r
door
har
dwar
e
incl
udin
g
mirr
or,
hi
nges
, lat
ch
and
win
dow
re
gula
tor
• P
rovi
de p
rope
r
surf
ace
for
ap
pear
ance
ite
ms
- P
aint
and
sof
t trim
Pot
entia
lF
ailu
reM
ode
Cor
rode
din
terio
rlo
wer
doo
rpa
nels
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lead
ing
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ougH
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
or
har
dwar
e
C l a s s
S e v 7 7 7 7 7
O c c u r 6 4 2 5 4
D e t e c 7 7 2 8 4
R.
P.
N.
294
196
28 280
112
S e v 7 7 7 7
R.
P.
N.
28 28 21 7
O c c 2 2 1 1
D e t 2 2 3 1
▲
▲
▲
▲
Act
ion
Res
ults
▲
Rec
omm
ende
dA
ctio
n(s)
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Con
duct
Des
ign
of E
xper
imen
ts(D
OE
) on
wax
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knes
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e
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n sp
ray
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ified
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team
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uatio
n us
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gn a
id b
uck
and
spra
y he
ad
Pot
entia
lC
ause
(s)/
Mec
hani
sm(s
)of
Fai
lure
Upp
er e
dge
ofpr
otec
tive
wax
appl
icat
ion
spec
ified
for
inne
r do
or p
anel
s is
too
low
Insu
ffici
ent w
axth
ickn
ess
spec
ified
Inap
prop
riate
wax
form
ulat
ion
spec
ified
Ent
rapp
ed a
ir pr
even
tsw
ax fr
om e
nter
ing
corn
er/e
dge
acce
ss
Insu
ffici
ent r
oom
betw
een
pane
ls fo
rsp
ray
head
acc
ess\
Act
ions
Tak
en
Bas
ed o
n te
stre
sults
(T
est N
o.14
81)
uppe
red
ge s
pec
rais
ed12
5mm
Tes
t res
ults
(Tes
t No.
148
1)sh
ow s
peci
fied
thic
knes
s is
adeq
uate
. D
OE
show
s 25
%va
riatio
n in
spec
ified
thic
knes
sis
acc
epta
ble.
Bas
ed o
n te
st, 3
addi
tiona
l ven
tho
les
prov
ided
inaf
fect
ed a
reas
Eva
luat
ion
show
edad
equa
te a
cces
s
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
A T
ate-
Bod
yE
ngrg
8X 0
9 3
0
Com
bine
w/te
stfo
r w
ax u
pper
edge
ver
ifica
tion
A T
ate
Bod
y E
ngrg
9X 0
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 1
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 0
9 15
8
9
1213
1416
1518
17
1920
21
22
Cor
e T
eam
T. F
ende
r-C
ar P
rodu
ct D
ev.,
Chi
lder
s-M
anuf
actu
ring,
J. F
ord-
Ass
y O
ps
(D
alto
n, F
rase
r, H
enle
y A
ssem
bly
Pla
nts)
Des
ign
Res
pons
ibili
ty B
ody
Eng
inee
ring
Key
Dat
e 9
X 0
3 0
1 E
R
FM
EA
Num
ber
1
234
Pag
e 1
of
1
Pre
pare
d B
y A
. T
ate
- X
6412
- B
ody
Eng
r
FM
EA
Dat
e (O
rig.)
8X
03
22
(
Rev
.) 8
X 0
7 1
4
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(DE
SIG
N F
ME
A)
Com
pone
nt 0
1.03
/Bod
y C
losu
res
MO
DE
L Y
EA
RS(S
)/V
ehic
le(s
) 1
99X
/Lio
n 4
dr/W
agon
23 6
7
11
10
5
Cur
rent
Des
ign
Con
trol
s
Det
ectio
n
Veh
icle
gen
eral
dur
abili
tyte
st v
eh.
T
-118
T
-109
T
-301
Veh
icle
gen
eral
dur
abili
tyte
stin
g- a
s ab
ove
Phy
sica
l and
Che
m L
abte
st-
Rep
ort N
o.12
65
Des
ign
aid
inve
stig
atio
nw
ith n
on-f
unct
ioni
ngsp
ray
head
Dra
win
g ev
alua
tion
of s
pray
hea
d ac
cess
Sys
tem
XS
ubsy
stem
Cur
rent
Des
ign
Con
trol
s
P
reve
ntio
n
16 SA
MP
LE
8) Core Team List the names of the responsible individuals and departmentsthat have the authority to identify and/or perform tasks. (It isrecommended that each team member's name, department,telephone number, addresse, etc., be included on a distributionlist.)
9) Item/Function Enter the name and other pertinent information (e.g., thenumber, the part class, etc.) of the item being analyzed. Use thenomenclature and show the design level as indicated on theengineering drawing. Prior to initial release (e.g., in theconceptual phases), experimental numbers should be used.
Enter, as concisely as possible, the function of the item beinganalyzed to meet the design intent. Include information (metrics/measurables) regarding the environment in which this systemoperates (e.g., define temperature, pressure, humidity ranges,design life). If the item has more than one function with differentpotential modes of failure, list all the functions separately.
10) Potential Failure Mode Potential failure mode is defined as the manner in which acomponent, subsystem, or system could potentially fail to meetor deliver the intended function described in the item/functioncolumn (i.e., intended function fails). The potential failure modemay also be the cause of a potential failure mode in a higher-level subsystem or system, or be the effect of one in a lower-level component.
List each potential failure mode associated with the particularitem and item function. The assumption is made that the failurecould occur but may not necessarily occur. A recommendedstarting point is a review of past things-gone-wrong, concerns,reports, and group brainstorming.
Potential failure modes that could occur only under certainoperating conditions (i.e., hot, cold, dry, dusty, etc.) and undercertain usage conditions (i.e., above-average mileage, roughterrain, city driving only, etc.) should be considered.
Typical failure modes could be but are not limited to:
Cracked DeformedLoosened LeakingSticking OxidizedFractured Does not transmit torqueSlips (does not hold full torque) No support (structural)Inadequate support (structural) Harsh engagementDisengages too fast Inadequate signalIntermittent signal No signalEMC/RFI Drift
NOTE: Potential failure modes should be described in“physical” or technical terms, not as a symptomnecessarily noticeable by the customer.
– 15 –
DESIGN FMEA
– 16 –
TABLE 1. DESIGN FMEA
Item
Fun
ctio
n
Fro
nt D
oor
L.H
.H
8HX
-000
0-A
• In
gres
s to
and
eg
ress
from
ve
hicl
e•
Occ
upan
t
prot
ectio
n
from
wea
ther
,
nois
e, a
nd
side
impa
ct
• S
uppo
rt
anch
orag
e fo
r
door
har
dwar
e
incl
udin
g
mirr
or,
hi
nges
, lat
ch
and
win
dow
re
gula
tor
• P
rovi
de p
rope
r
surf
ace
for
ap
pear
ance
ite
ms
- P
aint
and
sof
t trim
Pot
entia
lF
ailu
reM
ode
Cor
rode
din
terio
rlo
wer
doo
rpa
nels
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lead
ing
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ougH
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
or
har
dwar
e
C l a s s
S e v 7 7 7 7 7
O c c u r 6 4 2 5 4
D e t e c 7 7 2 8 4
R.
P.
N.
294
196
28 280
112
S e v 7 7 7 7
R.
P.
N.
28 28 21 7
O c c 2 2 1 1
D e t 2 2 3 1
▲
▲
▲
▲
Act
ion
Res
ults
▲
Rec
omm
ende
dA
ctio
n(s)
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Con
duct
Des
ign
of E
xper
imen
ts(D
OE
) on
wax
thic
knes
s
Non
e
Add
team
eval
uatio
n us
ing
prod
uctio
n sp
ray
equi
pmen
t and
spec
ified
wax
Add
team
eval
uatio
n us
ing
desi
gn a
id b
uck
and
spra
y he
ad
Pot
entia
lC
ause
(s)/
Mec
hani
sm(s
)of
Fai
lure
Upp
er e
dge
ofpr
otec
tive
wax
appl
icat
ion
spec
ified
for
inne
r do
or p
anel
s is
too
low
Insu
ffici
ent w
axth
ickn
ess
spec
ified
Inap
prop
riate
wax
form
ulat
ion
spec
ified
Ent
rapp
ed a
ir pr
even
tsw
ax fr
om e
nter
ing
corn
er/e
dge
acce
ss
Insu
ffici
ent r
oom
betw
een
pane
ls fo
rsp
ray
head
acc
ess\
Act
ions
Tak
en
Bas
ed o
n te
stre
sults
(T
est N
o.14
81)
uppe
red
ge s
pec
rais
ed12
5mm
Tes
t res
ults
(Tes
t No.
148
1)sh
ow s
peci
fied
thic
knes
s is
adeq
uate
. D
OE
show
s 25
%va
riatio
n in
spec
ified
thic
knes
sis
acc
epta
ble.
Bas
ed o
n te
st, 3
addi
tiona
l ven
tho
les
prov
ided
inaf
fect
ed a
reas
Eva
luat
ion
show
edad
equa
te a
cces
s
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
A T
ate-
Bod
yE
ngrg
8X 0
9 3
0
Com
bine
w/te
stfo
r w
ax u
pper
edge
ver
ifica
tion
A T
ate
Bod
y E
ngrg
9X 0
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 1
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 0
9 15
8
9
1213
1416
1518
17
1920
21
22
Cor
e T
eam
T. F
ende
r-C
ar P
rodu
ct D
ev.,
Chi
lder
s-M
anuf
actu
ring,
J. F
ord-
Ass
y O
ps
(D
alto
n, F
rase
r, H
enle
y A
ssem
bly
Pla
nts)
Des
ign
Res
pons
ibili
ty B
ody
Eng
inee
ring
Key
Dat
e 9
X 0
3 0
1 E
R
FM
EA
Num
ber
1
234
Pag
e 1
of
1
Pre
pare
d B
y A
. T
ate
- X
6412
- B
ody
Eng
r
FM
EA
Dat
e (O
rig.)
8X
03
22
(
Rev
.) 8
X 0
7 1
4
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(DE
SIG
N F
ME
A)
Com
pone
nt 0
1.03
/Bod
y C
losu
res
MO
DE
L Y
EA
RS(S
)/V
ehic
le(s
) 1
99X
/Lio
n 4
dr/W
agon
23 6
7
11
10
5
Cur
rent
Des
ign
Con
trol
s
Det
ectio
n
Veh
icle
gen
eral
dur
abili
tyte
st v
eh.
T
-118
T
-109
T
-301
Veh
icle
gen
eral
dur
abili
tyte
stin
g- a
s ab
ove
Phy
sica
l and
Che
m L
abte
st-
Rep
ort N
o.12
65
Des
ign
aid
inve
stig
atio
nw
ith n
on-f
unct
ioni
ngsp
ray
head
Dra
win
g ev
alua
tion
of s
pray
hea
d ac
cess
Sys
tem
XS
ubsy
stem
Cur
rent
Des
ign
Con
trol
s
P
reve
ntio
n
16 SA
MP
LE
– 17 –
11) Potential Effect(s) of Failure Potential effects of failure are defined as the effects of the failuremode on the function, as perceived by the customer.
Describe the effects of the failure in terms of what the customermight notice or experience, remembering that the customer maybe an internal customer as well as the ultimate end user. Stateclearly if the failure mode could impact safety or non-compliance to regulations. The effects should always be statedin terms of the specific system, subsystem, or component beinganalyzed. Remember that a hierarchical relationship existsbetween the component, subsystem, and system levels. Forexample, a part could fracture, which may cause the assemblyto vibrate, resulting in an intermittent system operation. Theintermittent system operation could cause performance todegrade and ultimately lead to customer dissatisfaction. Theintent is to forecast the failure effects, to the team’s level ofknowledge.
Typical failure effects could be but are not limited to:
Noise RoughErratic Operation InoperativePoor Appearance Unpleasant OdorUnstable Operation ImpairedIntermittent Operation Thermal EventLeaks Regulatory Non-Compliance
12) Severity (s) Severity is the rank associated with the most serious effect for agiven failure mode. Severity is a relative ranking within thescope of the individual FMEA. A reduction in the severityranking index can be effected only through a design change.Severity should be estimated using Table 2 as a guideline:
Suggested Evaluation CriteriaThe team should agree on an evaluation criteria and rankingsystem that is consistent, even if modified for individual productanalysis. (See Table 2.)
NOTE: It is not recommended to modify criteria rankingvalues of 9 and 10. Failure modes with a rank ofseverity 1 should not be analyzed further.
NOTE: High severity rankings can sometimes be reduced bymaking design revisions that compensate or mitigatethe resultant severity of failure. For example, “runflat tires” can mitigate the severity of a sudden tireblowout and “seat belts” can mitigate the severity ofa vehicle crash.
DESIGN FMEA
– 18 –
Table 1. DESIGN FMEA
Item
Fun
ctio
n
Fro
nt D
oor
L.H
.H
8HX
-000
0-A
• In
gres
s to
and
eg
ress
from
ve
hicl
e•
Occ
upan
t
prot
ectio
n
from
wea
ther
,
nois
e, a
nd
side
impa
ct
• S
uppo
rt
anch
orag
e fo
r
door
har
dwar
e
incl
udin
g
mirr
or,
hi
nges
, lat
ch
and
win
dow
re
gula
tor
• P
rovi
de p
rope
r
surf
ace
for
ap
pear
ance
ite
ms
- P
aint
and
sof
t trim
Pot
entia
lF
ailu
reM
ode
Cor
rode
din
terio
rlo
wer
doo
rpa
nels
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lead
ing
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ougH
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
or
har
dwar
e
C l a s s
S e v 7 7 7 7 7
O c c u r 6 4 2 5 4
D e t e c 7 7 2 8 4
R.
P.
N.
294
196
28 280
112
S e v 7 7 7 7
R.
P.
N.
28 28 21 7
O c c 2 2 1 1
D e t 2 2 3 1
▲
▲
▲
▲
Act
ion
Res
ults
▲
Rec
omm
ende
dA
ctio
n(s)
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Con
duct
Des
ign
of E
xper
imen
ts(D
OE
) on
wax
thic
knes
s
Non
e
Add
team
eval
uatio
n us
ing
prod
uctio
n sp
ray
equi
pmen
t and
spec
ified
wax
Add
team
eval
uatio
n us
ing
desi
gn a
id b
uck
and
spra
y he
ad
Pot
entia
lC
ause
(s)/
Mec
hani
sm(s
)of
Fai
lure
Upp
er e
dge
ofpr
otec
tive
wax
appl
icat
ion
spec
ified
for
inne
r do
or p
anel
s is
too
low
Insu
ffici
ent w
axth
ickn
ess
spec
ified
Inap
prop
riate
wax
form
ulat
ion
spec
ified
Ent
rapp
ed a
ir pr
even
tsw
ax fr
om e
nter
ing
corn
er/e
dge
acce
ss
Insu
ffici
ent r
oom
betw
een
pane
ls fo
rsp
ray
head
acc
ess\
Act
ions
Tak
en
Bas
ed o
n te
stre
sults
(T
est N
o.14
81)
uppe
red
ge s
pec
rais
ed12
5mm
Tes
t res
ults
(Tes
t No.
148
1)sh
ow s
peci
fied
thic
knes
s is
adeq
uate
. D
OE
show
s 25
%va
riatio
n in
spec
ified
thic
knes
sis
acc
epta
ble.
Bas
ed o
n te
st, 3
addi
tiona
l ven
tho
les
prov
ided
inaf
fect
ed a
reas
Eva
luat
ion
show
edad
equa
te a
cces
s
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
A T
ate-
Bod
yE
ngrg
8X 0
9 3
0
Com
bine
w/te
stfo
r w
ax u
pper
edge
ver
ifica
tion
A T
ate
Bod
y E
ngrg
9X 0
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 1
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 0
9 15
8
9
1213
1416
1518
17
1920
21
22
Cor
e T
eam
T. F
ende
r-C
ar P
rodu
ct D
ev.,
Chi
lder
s-M
anuf
actu
ring,
J. F
ord-
Ass
y O
ps
(D
alto
n, F
rase
r, H
enle
y A
ssem
bly
Pla
nts)
Des
ign
Res
pons
ibili
ty B
ody
Eng
inee
ring
Key
Dat
e 9
X 0
3 0
1 E
R
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(DE
SIG
N F
ME
A)
Com
pone
nt 0
1.03
/Bod
y C
losu
res
MO
DE
L Y
EA
RS(S
)/V
ehic
le(s
) 1
99X
/Lio
n 4
dr/W
agon
23 6
7
11
10
5
Cur
rent
Des
ign
Con
trol
s
Det
ectio
n
Veh
icle
gen
eral
dur
abili
tyte
st v
eh.
T
-118
T
-109
T
-301
Veh
icle
gen
eral
dur
abili
tyte
stin
g- a
s ab
ove
Phy
sica
l and
Che
m L
abte
st-
Rep
ort N
o.12
65
Des
ign
aid
inve
stig
atio
nw
ith n
on-f
unct
ioni
ngsp
ray
head
Dra
win
g ev
alua
tion
of s
pray
hea
d ac
cess
Sys
tem
XS
ubsy
stem
Cur
rent
Des
ign
Con
trol
s
P
reve
ntio
n
16 SA
MP
LE
FM
EA
Num
ber
1
234
Pag
e 1
of
1
Pre
pare
d B
y A
. T
ate
- X
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EA
Dat
e (O
rig.)
8X
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22
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Rev
.) 8
X 0
7 1
4
– 19 –
13) Classification This column may be used to classify any special productcharacteristics (e.g., critical, key, major, significant) forcomponents, subsystems, or systems that may requireadditional design or process controls.
This column may also be used to highlight high-priority failuremodes for engineering assessment if the team finds this helpfulor if local management requires it.
Special product or process characteristic symbols and theirusage is directed by specific company policy and is notstandardized in this document.
Potential cause of failure is defined as an indication of a designweakness, the consequence of which is the failure mode.
List, to the extent possible, every potential cause and/or failuremechanism for each failure mode. The cause/mechanismshould be listed as concisely and completely as possible so thatremedial efforts can be aimed at pertinent causes.
Effect
Hazardouswithoutwarning
Hazardouswith warning
Very High
High
Moderate
Low
Very Low
Minor
Very Minor
None
Very high severity ranking when a potential failure mode affects safe vehicleoperation and/or involves noncompliance with government regulation withoutwarning.
Very high severity ranking when a potential failure mode affects safe vehicleoperation and/or involves noncompliance with government regulation with warning.
Vehicle/item inoperable (loss of primary function).
Vehicle/item operable but at reduced level of performance. Customer verydissatisfied.
Vehicle/item operable, but Comfort/Convenience item(s) inoperable. Customerdissatisfied.
Vehicle/item operable, but Comfort/Convenience item(s) operable at a reducedlevel of performance. Customer somewhat dissatisfied.
Fit & Finish/Squeak & Rattle item does not conform. Defect noticed by mostcustomers (greater than 75%).
Fit & Finish/Squeak & Rattle item does not conform. Defect noticed by 50% ofcustomers.
Fit & Finish/Squeak & Rattle item does not conform. Defect noticed by discriminat-ing customers (less than 25%).
No discernible effect.
Criteria: Severity of Effect Ranking
10
9
8
7
6
5
4
3
2
1
Table 2. Suggested DFMEA Severity Evaluation Criteria
DESIGN FMEA
14) Potential Cause(s)/Mechanism(s) of Failure
12) Severity (S) (continued)
– 20 –
TABLE 1. DESIGN FMEA
Item
Fun
ctio
n
Fro
nt D
oor
L.H
.H
8HX
-000
0-A
• In
gres
s to
and
eg
ress
from
ve
hicl
e•
Occ
upan
t
prot
ectio
n
from
wea
ther
,
nois
e, a
nd
side
impa
ct
• S
uppo
rt
anch
orag
e fo
r
door
har
dwar
e
incl
udin
g
mirr
or,
hi
nges
, lat
ch
and
win
dow
re
gula
tor
• P
rovi
de p
rope
r
surf
ace
for
ap
pear
ance
ite
ms
- P
aint
and
sof
t trim
Pot
entia
lF
ailu
reM
ode
Cor
rode
din
terio
rlo
wer
doo
rpa
nels
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lead
ing
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ougH
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
or
har
dwar
e
C l a s s
S e v 7 7 7 7 7
O c c u r 6 4 2 5 4
D e t e c 7 7 2 8 4
R.
P.
N.
294
196
28 280
112
S e v 7 7 7 7
R.
P.
N.
28 28 21 7
O c c 2 2 1 1
D e t 2 2 3 1
▲
▲
▲
▲
Act
ion
Res
ults
▲
Rec
omm
ende
dA
ctio
n(s)
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Con
duct
Des
ign
of E
xper
imen
ts(D
OE
) on
wax
thic
knes
s
Non
e
Add
team
eval
uatio
n us
ing
prod
uctio
n sp
ray
equi
pmen
t and
spec
ified
wax
Add
team
eval
uatio
n us
ing
desi
gn a
id b
uck
and
spra
y he
ad
Pot
entia
lC
ause
(s)/
Mec
hani
sm(s
)of
Fai
lure
Upp
er e
dge
ofpr
otec
tive
wax
appl
icat
ion
spec
ified
for
inne
r do
or p
anel
s is
too
low
Insu
ffici
ent w
axth
ickn
ess
spec
ified
Inap
prop
riate
wax
form
ulat
ion
spec
ified
Ent
rapp
ed a
ir pr
even
tsw
ax fr
om e
nter
ing
corn
er/e
dge
acce
ss
Insu
ffici
ent r
oom
betw
een
pane
ls fo
rsp
ray
head
acc
ess\
Act
ions
Tak
en
Bas
ed o
n te
stre
sults
(T
est N
o.14
81)
uppe
red
ge s
pec
rais
ed12
5mm
Tes
t res
ults
(Tes
t No.
148
1)sh
ow s
peci
fied
thic
knes
s is
adeq
uate
. D
OE
show
s 25
%va
riatio
n in
spec
ified
thic
knes
sis
acc
epta
ble.
Bas
ed o
n te
st, 3
addi
tiona
l ven
tho
les
prov
ided
inaf
fect
ed a
reas
Eva
luat
ion
show
edad
equa
te a
cces
s
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
A T
ate-
Bod
yE
ngrg
8X 0
9 3
0
Com
bine
w/te
stfo
r w
ax u
pper
edge
ver
ifica
tion
A T
ate
Bod
y E
ngrg
9X 0
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 1
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 0
9 15
8
9
1213
1416
1518
17
1920
21
22
Cor
e T
eam
T. F
ende
r-C
ar P
rodu
ct D
ev.,
Chi
lder
s-M
anuf
actu
ring,
J. F
ord-
Ass
y O
ps
(D
alto
n, F
rase
r, H
enle
y A
ssem
bly
Pla
nts)
Des
ign
Res
pons
ibili
ty B
ody
Eng
inee
ring
Key
Dat
e 9
X 0
3 0
1 E
R
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(DE
SIG
N F
ME
A)
Com
pone
nt 0
1.03
/Bod
y C
losu
res
MO
DE
L Y
EA
RS(S
)/V
ehic
le(s
) 1
99X
/Lio
n 4
dr/W
agon
23 6
7
11
10
5
Cur
rent
Des
ign
Con
trol
s
Det
ectio
n
Veh
icle
gen
eral
dur
abili
tyte
st v
eh.
T
-118
T
-109
T
-301
Veh
icle
gen
eral
dur
abili
tyte
stin
g- a
s ab
ove
Phy
sica
l and
Che
m L
abte
st-
Rep
ort N
o.12
65
Des
ign
aid
inve
stig
atio
nw
ith n
on-f
unct
ioni
ngsp
ray
head
Dra
win
g ev
alua
tion
of s
pray
hea
d ac
cess
Sys
tem
XS
ubsy
stem
Cur
rent
Des
ign
Con
trol
s
P
reve
ntio
n
16 SA
MP
LE
FM
EA
Num
ber
1
234
Pag
e 1
of
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Pre
pare
d B
y A
. T
ate
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ody
Eng
r
FM
EA
Dat
e (O
rig.)
8X
03
22
(
Rev
.) 8
X 0
7 1
4
– 21 –
Typical failure causes may include, but are not limited to:
Incorrect Material SpecifiedInadequate Design Life AssumptionOver-stressingInsufficient Lubrication CapabilityInadequate Maintenance InstructionsIncorrect AlgorithmImproper Maintenance InstructionsImproper Software SpecificationImproper Surface Finish SpecificationInadequate Travel SpecificationImproper Friction Material SpecifiedExcessive HeatImproper Tolerance Specified
Typical failure mechanisms may include but are not limited to:Yield Chemical OxidationFatigue ElectromigrationMaterial InstabilityCreepWearCorrosion
15) Occurrence (O) Occurrence is the likelihood that a specific cause/mechanismwill occur during the design life. The likelihood of occurrenceranking number has a relative meaning rather than an absolutevalue. Preventing or controlling the causes/mechanisms of thefailure mode through a design change or design processchange (e.g., design checklist, design review, design guide) isthe only way a reduction in the occurrence ranking can beeffected. (See Table 3.)
Estimate the likelihood of occurrence of potential failure cause/mechanism on a 1 to 10 scale. In determining this estimate,questions such as the following should be considered:
• What is the service history/field experience with similarcomponents, subsystems, or systems?
• Is the component a carryover or similar to a previouslevel component, subsystem or system?
• How significant are changes from a previous levelcomponent, subsystem, or system?
• Is the component radically different from a previouslevel component?
• Is the component completely new?• Has the component application changed?• What are the environmental changes?• Has an engineering analysis (e.g., reliability) been used
to estimate the expected comparable occurrence ratefor the application?
• Have preventive controls been put in place?
DESIGN FMEA
14) Potential Cause(s)/Mechanism(s) of Failure(continued)
– 22 –
TABLE 1. DESIGN FMEA
Item
Fun
ctio
n
Fro
nt D
oor
L.H
.H
8HX
-000
0-A
• In
gres
s to
and
eg
ress
from
ve
hicl
e•
Occ
upan
t
prot
ectio
n
from
wea
ther
,
nois
e, a
nd
side
impa
ct
• S
uppo
rt
anch
orag
e fo
r
door
har
dwar
e
incl
udin
g
mirr
or,
hi
nges
, lat
ch
and
win
dow
re
gula
tor
• P
rovi
de p
rope
r
surf
ace
for
ap
pear
ance
ite
ms
- P
aint
and
sof
t trim
Pot
entia
lF
ailu
reM
ode
Cor
rode
din
terio
rlo
wer
doo
rpa
nels
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lead
ing
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ougH
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
or
har
dwar
e
C l a s s
S e v 7 7 7 7 7
O c c u r 6 4 2 5 4
D e t e c 7 7 2 8 4
R.
P.
N.
294
196
28 280
112
S e v 7 7 7 7
R.
P.
N.
28 28 21 7
O c c 2 2 1 1
D e t 2 2 3 1
▲
▲
▲
▲
Act
ion
Res
ults
▲
Rec
omm
ende
dA
ctio
n(s)
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Con
duct
Des
ign
of E
xper
imen
ts(D
OE
) on
wax
thic
knes
s
Non
e
Add
team
eval
uatio
n us
ing
prod
uctio
n sp
ray
equi
pmen
t and
spec
ified
wax
Add
team
eval
uatio
n us
ing
desi
gn a
id b
uck
and
spra
y he
ad
Pot
entia
lC
ause
(s)/
Mec
hani
sm(s
)of
Fai
lure
Upp
er e
dge
ofpr
otec
tive
wax
appl
icat
ion
spec
ified
for
inne
r do
or p
anel
s is
too
low
Insu
ffici
ent w
axth
ickn
ess
spec
ified
Inap
prop
riate
wax
form
ulat
ion
spec
ified
Ent
rapp
ed a
ir pr
even
tsw
ax fr
om e
nter
ing
corn
er/e
dge
acce
ss
Insu
ffici
ent r
oom
betw
een
pane
ls fo
rsp
ray
head
acc
ess\
Act
ions
Tak
en
Bas
ed o
n te
stre
sults
(T
est N
o.14
81)
uppe
red
ge s
pec
rais
ed12
5mm
Tes
t res
ults
(Tes
t No.
148
1)sh
ow s
peci
fied
thic
knes
s is
adeq
uate
. D
OE
show
s 25
%va
riatio
n in
spec
ified
thic
knes
sis
acc
epta
ble.
Bas
ed o
n te
st, 3
addi
tiona
l ven
tho
les
prov
ided
inaf
fect
ed a
reas
Eva
luat
ion
show
edad
equa
te a
cces
s
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
A T
ate-
Bod
yE
ngrg
8X 0
9 3
0
Com
bine
w/te
stfo
r w
ax u
pper
edge
ver
ifica
tion
A T
ate
Bod
y E
ngrg
9X 0
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 1
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 0
9 15
8
9
1213
1416
1518
17
1920
21
22
Cor
e T
eam
T. F
ende
r-C
ar P
rodu
ct D
ev.,
Chi
lder
s-M
anuf
actu
ring,
J. F
ord-
Ass
y O
ps
(D
alto
n, F
rase
r, H
enle
y A
ssem
bly
Pla
nts)
Des
ign
Res
pons
ibili
ty B
ody
Eng
inee
ring
Key
Dat
e 9
X 0
3 0
1 E
R
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(DE
SIG
N F
ME
A)
Com
pone
nt 0
1.03
/Bod
y C
losu
res
MO
DE
L Y
EA
RS(S
)/V
ehic
le(s
) 1
99X
/Lio
n 4
dr/W
agon
23 6
7
11
10
5
Cur
rent
Des
ign
Con
trol
s
Det
ectio
n
Veh
icle
gen
eral
dur
abili
tyte
st v
eh.
T
-118
T
-109
T
-301
Veh
icle
gen
eral
dur
abili
tyte
stin
g- a
s ab
ove
Phy
sica
l and
Che
m L
abte
st-
Rep
ort N
o.12
65
Des
ign
aid
inve
stig
atio
nw
ith n
on-f
unct
ioni
ngsp
ray
head
Dra
win
g ev
alua
tion
of s
pray
hea
d ac
cess
Sys
tem
XS
ubsy
stem
Cur
rent
Des
ign
Con
trol
s
P
reve
ntio
n
16 SA
MP
LE
FM
EA
Num
ber
1
234
Pag
e 1
of
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Pre
pare
d B
y A
. T
ate
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6412
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ody
Eng
r
FM
EA
Dat
e (O
rig.)
8X
03
22
(
Rev
.) 8
X 0
7 1
4
– 23 –
A consistent occurrence ranking system should be used toensure continuity. The occurrence ranking number is a relativerating within the scope of the FMEA and may not reflect theactual likelihood of occurrence.
Suggested Evaluation CriteriaThe team should agree on an evaluation criteria and rankingsystem, that is consistent, even if modified for individual productanalysis. (See Table 3.) Occurrence should be estimated usingTable 3 as a guideline:
NOTE: The ranking value of 1 is reserved for “Remote: FailureIs unlikely.”
RankingPossible Failure Rates
10
9
8
7
6
5
4
3
2
1
> 100 per thousand vehicles/items
50 per thousand vehicles/items
20 per thousand vehicles/items
10 per thousand vehicles/items
5 per thousand vehicles/items
2 per thousand vehicles/items
1 per thousand vehicles/items
0.5 per thousand vehicles/items
0.1 per thousand vehicles/items
< 0.010 per thousand vehicles/items
Very High: Persistent failures
High: Frequent failures
Moderate: Occasional failures
Low: Relatively few failures
Remote: Failure is unlikely
Probability of Failure
TABLE 3. Suggested DFMEA Occurrence Evaluation Criteria
16) Current Design Controls List the prevention, design validation/verification (DV), or otheractivities that have been completed or committed to and thatwill assure the design adequacy for the failure mode and/orcause/mechanism under consideration. Current controls (e.g.,design reviews, fail/safe designs such as a pressure relief valve,mathematical studies, rig/lab testing, feasibility review,prototype tests, road testing, fleet testing) are those that havebeen or are being used with the same or similar designs. Theteam should always be focused on improving design controls;for example, creating new system tests in the lab, or creatingnew system modeling algorithms, etc.
There are two types of design controls to consider:
Prevention: Prevent the cause/mechanism of failure or thefailure mode from occurring, or reduce theirrate of occurrence,
Detection: Detect the cause/mechanism of failure or thefailure mode, either by analytical or physicalmethods, before the item is released toproduction.
DESIGN FMEA
15) Occurrence (O)(continued)
– 24 –
TABLE 1. DESIGN FMEA
Item
Fun
ctio
n
Fro
nt D
oor
L.H
.H
8HX
-000
0-A
• In
gres
s to
and
eg
ress
from
ve
hicl
e•
Occ
upan
t
prot
ectio
n
from
wea
ther
,
nois
e, a
nd
side
impa
ct
• S
uppo
rt
anch
orag
e fo
r
door
har
dwar
e
incl
udin
g
mirr
or,
hi
nges
, lat
ch
and
win
dow
re
gula
tor
• P
rovi
de p
rope
r
surf
ace
for
ap
pear
ance
ite
ms
- P
aint
and
sof
t trim
Pot
entia
lF
ailu
reM
ode
Cor
rode
din
terio
rlo
wer
doo
rpa
nels
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lead
ing
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ougH
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
or
har
dwar
e
C l a s s
S e v 7 7 7 7 7
O c c u r 6 4 2 5 4
D e t e c 7 7 2 8 4
R.
P.
N.
294
196
28 280
112
S e v 7 7 7 7
R.
P.
N.
28 28 21 7
O c c 2 2 1 1
D e t 2 2 3 1
▲
▲
▲
▲
Act
ion
Res
ults
▲
Rec
omm
ende
dA
ctio
n(s)
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Con
duct
Des
ign
of E
xper
imen
ts(D
OE
) on
wax
thic
knes
s
Non
e
Add
team
eval
uatio
n us
ing
prod
uctio
n sp
ray
equi
pmen
t and
spec
ified
wax
Add
team
eval
uatio
n us
ing
desi
gn a
id b
uck
and
spra
y he
ad
Pot
entia
lC
ause
(s)/
Mec
hani
sm(s
)of
Fai
lure
Upp
er e
dge
ofpr
otec
tive
wax
appl
icat
ion
spec
ified
for
inne
r do
or p
anel
s is
too
low
Insu
ffici
ent w
axth
ickn
ess
spec
ified
Inap
prop
riate
wax
form
ulat
ion
spec
ified
Ent
rapp
ed a
ir pr
even
tsw
ax fr
om e
nter
ing
corn
er/e
dge
acce
ss
Insu
ffici
ent r
oom
betw
een
pane
ls fo
rsp
ray
head
acc
ess\
Act
ions
Tak
en
Bas
ed o
n te
stre
sults
(T
est N
o.14
81)
uppe
red
ge s
pec
rais
ed12
5mm
Tes
t res
ults
(Tes
t No.
148
1)sh
ow s
peci
fied
thic
knes
s is
adeq
uate
. D
OE
show
s 25
%va
riatio
n in
spec
ified
thic
knes
sis
acc
epta
ble.
Bas
ed o
n te
st, 3
addi
tiona
l ven
tho
les
prov
ided
inaf
fect
ed a
reas
Eva
luat
ion
show
edad
equa
te a
cces
s
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
A T
ate-
Bod
yE
ngrg
8X 0
9 3
0
Com
bine
w/te
stfo
r w
ax u
pper
edge
ver
ifica
tion
A T
ate
Bod
y E
ngrg
9X 0
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 1
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 0
9 15
8
9
1213
1416
1518
17
1920
21
22
Cor
e T
eam
T. F
ende
r-C
ar P
rodu
ct D
ev.,
Chi
lder
s-M
anuf
actu
ring,
J. F
ord-
Ass
y O
ps
(D
alto
n, F
rase
r, H
enle
y A
ssem
bly
Pla
nts)
Des
ign
Res
pons
ibili
ty B
ody
Eng
inee
ring
Key
Dat
e 9
X 0
3 0
1 E
R
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(DE
SIG
N F
ME
A)
Com
pone
nt 0
1.03
/Bod
y C
losu
res
MO
DE
L Y
EA
RS(S
)/V
ehic
le(s
) 1
99X
/Lio
n 4
dr/W
agon
23 6
7
11
10
5
Cur
rent
Des
ign
Con
trol
s
Det
ectio
n
Veh
icle
gen
eral
dur
abili
tyte
st v
eh.
T
-118
T
-109
T
-301
Veh
icle
gen
eral
dur
abili
tyte
stin
g- a
s ab
ove
Phy
sica
l and
Che
m L
abte
st-
Rep
ort N
o.12
65
Des
ign
aid
inve
stig
atio
nw
ith n
on-f
unct
ioni
ngsp
ray
head
Dra
win
g ev
alua
tion
of s
pray
hea
d ac
cess
Sys
tem
XS
ubsy
stem
Cur
rent
Des
ign
Con
trol
s
P
reve
ntio
n
16 SA
MP
LE
FM
EA
Num
ber
1
234
Pag
e 1
of
1
Pre
pare
d B
y A
. T
ate
- X
6412
- B
ody
Eng
r
FM
EA
Dat
e (O
rig.)
8X
03
22
(
Rev
.) 8
X 0
7 1
4
– 25 –
DESIGN FMEA
16) Current Design Controls(continued)
The preferred approach is to first use prevention controls, ifpossible. The initial occurrence rankings will be affected by theprevention controls provided they are integrated as part of thedesign intent. The initial rankings for detection will be based ondesign controls that either detect the cause/mechanism offailure, or detect the failure mode.
The Design FMEA form in this manual has two columns for thedesign controls (i.e., separate columns for Prevention Controlsand Detection Controls) to assist the team in clearlydistinguishing between these two types of design controls. Thisallows for a quick visual determination that both types of designcontrols have been considered. Use of this two-column form isthe preferred approach.
Note: In the example included here, it is clear that the teamhas not identified any prevention controls. This couldbe due to prevention controls not having been usedon the same or similar designs.
If a one-column (for design controls) form is used, then thefollowing prefixes should be used. For prevention controls,place a 'P' before each prevention control listed. For detectioncontrols, place a 'D' before each detection control listed.
Once the design controls have been identified, review allprevention controls to determine if any occurrence rankingsneed to be revised.
17) Detection (D) Detection is the rank associated with the best detection controllisted in the design control. Detection is a relative ranking,within the scope of the individual FMEA. In order to achieve alower ranking, generally the planned design control (e.g.,validation, and/or verification activities) has to be improved.
– 26 –
TABLE 1. DESIGN FMEA
Item
Fun
ctio
n
Fro
nt D
oor
L.H
.H
8HX
-000
0-A
• In
gres
s to
and
eg
ress
from
ve
hicl
e•
Occ
upan
t
prot
ectio
n
from
wea
ther
,
nois
e, a
nd
side
impa
ct
• S
uppo
rt
anch
orag
e fo
r
door
har
dwar
e
incl
udin
g
mirr
or,
hi
nges
, lat
ch
and
win
dow
re
gula
tor
• P
rovi
de p
rope
r
surf
ace
for
ap
pear
ance
ite
ms
- P
aint
and
sof
t trim
Pot
entia
lF
ailu
reM
ode
Cor
rode
din
terio
rlo
wer
doo
rpa
nels
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lead
ing
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ougH
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
or
har
dwar
e
C l a s s
S e v 7 7 7 7 7
O c c u r 6 4 2 5 4
D e t e c 7 7 2 8 4
R.
P.
N.
294
196
28 280
112
S e v 7 7 7 7
R.
P.
N.
28 28 21 7
O c c 2 2 1 1
D e t 2 2 3 1
▲
▲
▲
▲
Act
ion
Res
ults
▲
Rec
omm
ende
dA
ctio
n(s)
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Con
duct
Des
ign
of E
xper
imen
ts(D
OE
) on
wax
thic
knes
s
Non
e
Add
team
eval
uatio
n us
ing
prod
uctio
n sp
ray
equi
pmen
t and
spec
ified
wax
Add
team
eval
uatio
n us
ing
desi
gn a
id b
uck
and
spra
y he
ad
Pot
entia
lC
ause
(s)/
Mec
hani
sm(s
)of
Fai
lure
Upp
er e
dge
ofpr
otec
tive
wax
appl
icat
ion
spec
ified
for
inne
r do
or p
anel
s is
too
low
Insu
ffici
ent w
axth
ickn
ess
spec
ified
Inap
prop
riate
wax
form
ulat
ion
spec
ified
Ent
rapp
ed a
ir pr
even
tsw
ax fr
om e
nter
ing
corn
er/e
dge
acce
ss
Insu
ffici
ent r
oom
betw
een
pane
ls fo
rsp
ray
head
acc
ess\
Act
ions
Tak
en
Bas
ed o
n te
stre
sults
(T
est N
o.14
81)
uppe
red
ge s
pec
rais
ed12
5mm
Tes
t res
ults
(Tes
t No.
148
1)sh
ow s
peci
fied
thic
knes
s is
adeq
uate
. D
OE
show
s 25
%va
riatio
n in
spec
ified
thic
knes
sis
acc
epta
ble.
Bas
ed o
n te
st, 3
addi
tiona
l ven
tho
les
prov
ided
inaf
fect
ed a
reas
Eva
luat
ion
show
edad
equa
te a
cces
s
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
A T
ate-
Bod
yE
ngrg
8X 0
9 3
0
Com
bine
w/te
stfo
r w
ax u
pper
edge
ver
ifica
tion
A T
ate
Bod
y E
ngrg
9X 0
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 1
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 0
9 15
8
9
1213
1416
1518
17
1920
21
22
Cor
e T
eam
T. F
ende
r-C
ar P
rodu
ct D
ev.,
Chi
lder
s-M
anuf
actu
ring,
J. F
ord-
Ass
y O
ps
(D
alto
n, F
rase
r, H
enle
y A
ssem
bly
Pla
nts)
Des
ign
Res
pons
ibili
ty B
ody
Eng
inee
ring
Key
Dat
e 9
X 0
3 0
1 E
R
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(DE
SIG
N F
ME
A)
Com
pone
nt 0
1.03
/Bod
y C
losu
res
MO
DE
L Y
EA
RS(S
)/V
ehic
le(s
) 1
99X
/Lio
n 4
dr/W
agon
23 6
7
11
10
5
Cur
rent
Des
ign
Con
trol
s
Det
ectio
n
Veh
icle
gen
eral
dur
abili
tyte
st v
eh.
T
-118
T
-109
T
-301
Veh
icle
gen
eral
dur
abili
tyte
stin
g- a
s ab
ove
Phy
sica
l and
Che
m L
abte
st-
Rep
ort N
o.12
65
Des
ign
aid
inve
stig
atio
nw
ith n
on-f
unct
ioni
ngsp
ray
head
Dra
win
g ev
alua
tion
of s
pray
hea
d ac
cess
Sys
tem
XS
ubsy
stem
Cur
rent
Des
ign
Con
trol
s
P
reve
ntio
n
16 SA
MP
LE
FM
EA
Num
ber
1
234
Pag
e 1
of
1
Pre
pare
d B
y A
. T
ate
- X
6412
- B
ody
Eng
r
FM
EA
Dat
e (O
rig.)
8X
03
22
(
Rev
.) 8
X 0
7 1
4
– 27 –
DESIGN FMEA
Suggested Evaluation CriteriaThe team should agree on an evaluation criteria and rankingsystem that is consistent, even if modified for individual productanalysis.
It is best to have detection controls in place as early as possiblein the design development process.
NOTE: After making the detection ranking, the team shouldreview the occurrence ranking and ensure that theoccurrence ranking is still appropriate.
Detection should be estimated using Table 4 as a guideline.
NOTE: The ranking value of 1 is reserved for “almostcertain.”
Detection
AbsoluteUncertainty
Very Remote
Remote
Very Low
Low
Moderate
ModeratelyHigh
High
Very High
AlmostCertain
Design Control will not and/or can not detect a potential cause/mechanism andsubsequent failure mode; or there is no Design Control.
Very remote chance the Design Control will detect a potential cause/mechanismand subsequent failure mode.
Remote chance the Design Control will detect a potential cause/mechanism andsubsequent failure mode.
Very low chance the Design Control will detect a potential cause/mechanism andsubsequent failure mode.
Low chance the Design Control will detect a potential cause/mechanismand subsequent failure mode.
Moderate chance the Design Control will detect a potential cause/mechanism andsubsequent failure mode.
Moderately high chance the Design Control will detect a potential cause/ mecha-nism and subsequent failure mode.
High chance the Design Control will detect a potential cause/mechanism andsubsequent failure mode.
Very high chance the Design Control will detect a potential cause/mechanismand subsequent failure mode.
Design Control will almost certainly detect a potential cause/mechanism andsubsequent failure mode.
10
9
8
7
6
5
4
3
2
1
Criteria: Likelihood of Detection by Design Control Ranking
TABLE 4. Suggested Detection Evaluation Criteria
18) Risk Priority Number (RPN) The risk priority number is the product of the severity (S),occurrence (O), and detection (D) rankings.
(S) x (O) x (D) = RPN
Within the scope of the individual FMEA, this value (between 1and 1000) can be used to rank order the concerns in the design.
– 28 –
TABLE 1. DESIGN FMEA
Item
Fun
ctio
n
Fro
nt D
oor
L.H
.H
8HX
-000
0-A
• In
gres
s to
and
eg
ress
from
ve
hicl
e•
Occ
upan
t
prot
ectio
n
from
wea
ther
,
nois
e, a
nd
side
impa
ct
• S
uppo
rt
anch
orag
e fo
r
door
har
dwar
e
incl
udin
g
mirr
or,
hi
nges
, lat
ch
and
win
dow
re
gula
tor
• P
rovi
de p
rope
r
surf
ace
for
ap
pear
ance
ite
ms
- P
aint
and
sof
t trim
Pot
entia
lF
ailu
reM
ode
Cor
rode
din
terio
rlo
wer
doo
rpa
nels
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lead
ing
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ougH
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
or
har
dwar
e
C l a s s
S e v 7 7 7 7 7
O c c u r 6 4 2 5 4
D e t e c 7 7 2 8 4
R.
P.
N.
294
196
28 280
112
S e v 7 7 7 7
R.
P.
N.
28 28 21 7
O c c 2 2 1 1
D e t 2 2 3 1
▲
▲
▲
▲
Act
ion
Res
ults
▲
Rec
omm
ende
dA
ctio
n(s)
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Con
duct
Des
ign
of E
xper
imen
ts(D
OE
) on
wax
thic
knes
s
Non
e
Add
team
eval
uatio
n us
ing
prod
uctio
n sp
ray
equi
pmen
t and
spec
ified
wax
Add
team
eval
uatio
n us
ing
desi
gn a
id b
uck
and
spra
y he
ad
Pot
entia
lC
ause
(s)/
Mec
hani
sm(s
)of
Fai
lure
Upp
er e
dge
ofpr
otec
tive
wax
appl
icat
ion
spec
ified
for
inne
r do
or p
anel
s is
too
low
Insu
ffici
ent w
axth
ickn
ess
spec
ified
Inap
prop
riate
wax
form
ulat
ion
spec
ified
Ent
rapp
ed a
ir pr
even
tsw
ax fr
om e
nter
ing
corn
er/e
dge
acce
ss
Insu
ffici
ent r
oom
betw
een
pane
ls fo
rsp
ray
head
acc
ess\
Act
ions
Tak
en
Bas
ed o
n te
stre
sults
(T
est N
o.14
81)
uppe
red
ge s
pec
rais
ed12
5mm
Tes
t res
ults
(Tes
t No.
148
1)sh
ow s
peci
fied
thic
knes
s is
adeq
uate
. D
OE
show
s 25
%va
riatio
n in
spec
ified
thic
knes
sis
acc
epta
ble.
Bas
ed o
n te
st, 3
addi
tiona
l ven
tho
les
prov
ided
inaf
fect
ed a
reas
Eva
luat
ion
show
edad
equa
te a
cces
s
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
A T
ate-
Bod
yE
ngrg
8X 0
9 3
0
Com
bine
w/te
stfo
r w
ax u
pper
edge
ver
ifica
tion
A T
ate
Bod
y E
ngrg
9X 0
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 1
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 0
9 15
8
9
1213
1416
1518
17
1920
21
22
Cor
e T
eam
T. F
ende
r-C
ar P
rodu
ct D
ev.,
Chi
lder
s-M
anuf
actu
ring,
J. F
ord-
Ass
y O
ps
(D
alto
n, F
rase
r, H
enle
y A
ssem
bly
Pla
nts)
Des
ign
Res
pons
ibili
ty B
ody
Eng
inee
ring
Key
Dat
e 9
X 0
3 0
1 E
R
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(DE
SIG
N F
ME
A)
Com
pone
nt 0
1.03
/Bod
y C
losu
res
MO
DE
L Y
EA
RS(S
)/V
ehic
le(s
) 1
99X
/Lio
n 4
dr/W
agon
23 6
7
11
10
5
Cur
rent
Des
ign
Con
trol
s
Det
ectio
n
Veh
icle
gen
eral
dur
abili
tyte
st v
eh.
T
-118
T
-109
T
-301
Veh
icle
gen
eral
dur
abili
tyte
stin
g- a
s ab
ove
Phy
sica
l and
Che
m L
abte
st-
Rep
ort N
o.12
65
Des
ign
aid
inve
stig
atio
nw
ith n
on-f
unct
ioni
ngsp
ray
head
Dra
win
g ev
alua
tion
of s
pray
hea
d ac
cess
Sys
tem
XS
ubsy
stem
Cur
rent
Des
ign
Con
trol
s
P
reve
ntio
n
16 SA
MP
LE
FM
EA
Num
ber
1
234
Pag
e 1
of
1
Pre
pare
d B
y A
. T
ate
- X
6412
- B
ody
Eng
r
FM
EA
Dat
e (O
rig.)
8X
03
22
(
Rev
.) 8
X 0
7 1
4
– 29 –
DESIGN FMEA
19) Recommended Action(s) Engineering assessment for preventive/corrective action shouldbe first directed at high severity, high RPN, and other itemsdesignated by the team. The intent of any recommended actionis to reduce rankings in the following order: severity,occurrence, and detection.
In general practice when the severity is a 9 or 10, specialattention must be given to ensure that the risk is addressedthrough existing design controls or preventive/correctiveaction(s), regardless of the RPN. In all cases where the effect ofan identified potential failure mode could be a hazard to the enduser, preventive/corrective actions should be considered toavoid the failure mode by eliminating, mitigating, or controllingthe cause(s).
After special attention has been given to severity rankings of 9or 10, the team then addresses other failure modes, with theintent of reducing severity, then occurrence, and then detection.
Actions such as, but not limited to, the following should beconsidered:
• Revised Design Geometry and/or Tolerances,• Revised Material Specification,• Design of Experiments (particularly when multiple or
interactive causes are present) or other problem-solvingtechniques, and,
• Revised Test Plan.
The primary objective of recommended actions is to reducerisks and increase customer satisfaction by improving thedesign.
Only a design revision can bring about a reduction in theseverity ranking. A reduction in the occurrence ranking can beeffected only by removing or controlling one or more of thecauses/mechanisms of the failure mode through a designrevision. An increase in design validation/verification actions willresult in a reduction in the detection ranking only. Increasingthe design validation/verification actions is a less desirableengineering action since it does not address the severity oroccurrence of the failure mode.
If engineering assessment leads to no recommended actions fora specific failure mode/cause/control combination, indicate thisby entering “None” in this column.
Enter the name of organization and individual responsible foreach recommended action and the target completion date.
20) Responsibility for theRecommended Action(s)
– 30 –
DESIGN FMEA
Item
Fun
ctio
n
Fro
nt D
oor
L.H
.H
8HX
-000
0-A
• In
gres
s to
and
eg
ress
from
ve
hicl
e•
Occ
upan
t
prot
ectio
n
from
wea
ther
,
nois
e, a
nd
side
impa
ct
• S
uppo
rt
anch
orag
e fo
r
door
har
dwar
e
incl
udin
g
mirr
or,
hi
nges
, lat
ch
and
win
dow
re
gula
tor
• P
rovi
de p
rope
r
surf
ace
for
ap
pear
ance
ite
ms
- P
aint
and
sof
t trim
Pot
entia
lF
ailu
reM
ode
Cor
rode
din
terio
rlo
wer
doo
rpa
nels
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lead
ing
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ougH
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
or
har
dwar
e
C l a s s
S e v 7 7 7 7 7
O c c u r 6 4 2 5 4
D e t e c 7 7 2 8 4
R.
P.
N.
294
196
28 280
112
S e v 7 7 7 7
R.
P.
N.
28 28 21 7
O c c 2 2 1 1
D e t 2 2 3 1
▲
▲
▲
▲
Act
ion
Res
ults
▲
Rec
omm
ende
dA
ctio
n(s)
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Con
duct
Des
ign
of E
xper
imen
ts(D
OE
) on
wax
thic
knes
s
Non
e
Add
team
eval
uatio
n us
ing
prod
uctio
n sp
ray
equi
pmen
t and
spec
ified
wax
Add
team
eval
uatio
n us
ing
desi
gn a
id b
uck
and
spra
y he
ad
Pot
entia
lC
ause
(s)/
Mec
hani
sm(s
)of
Fai
lure
Upp
er e
dge
ofpr
otec
tive
wax
appl
icat
ion
spec
ified
for
inne
r do
or p
anel
s is
too
low
Insu
ffici
ent w
axth
ickn
ess
spec
ified
Inap
prop
riate
wax
form
ulat
ion
spec
ified
Ent
rapp
ed a
ir pr
even
tsw
ax fr
om e
nter
ing
corn
er/e
dge
acce
ss
Insu
ffici
ent r
oom
betw
een
pane
ls fo
rsp
ray
head
acc
ess\
Act
ions
Tak
en
Bas
ed o
n te
stre
sults
(T
est N
o.14
81)
uppe
red
ge s
pec
rais
ed12
5mm
Tes
t res
ults
(Tes
t No.
148
1)sh
ow s
peci
fied
thic
knes
s is
adeq
uate
. D
OE
show
s 25
%va
riatio
n in
spec
ified
thic
knes
sis
acc
epta
ble.
Bas
ed o
n te
st, 3
addi
tiona
l ven
tho
les
prov
ided
inaf
fect
ed a
reas
Eva
luat
ion
show
edad
equa
te a
cces
s
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
A T
ate-
Bod
yE
ngrg
8X 0
9 3
0
Com
bine
w/te
stfo
r w
ax u
pper
edge
ver
ifica
tion
A T
ate
Bod
y E
ngrg
9X 0
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 1
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 0
9 15
8
9
1213
1416
1518
17
1920
21
22
Cor
e T
eam
T. F
ende
r-C
ar P
rodu
ct D
ev.,
Chi
lder
s-M
anuf
actu
ring,
J. F
ord-
Ass
y O
ps
(D
alto
n, F
rase
r, H
enle
y A
ssem
bly
Pla
nts)
Des
ign
Res
pons
ibili
ty B
ody
Eng
inee
ring
Key
Dat
e 9
X 0
3 0
1 E
R
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(DE
SIG
N F
ME
A)
Com
pone
nt 0
1.03
/Bod
y C
losu
res
MO
DE
L Y
EA
RS(S
)/V
ehic
le(s
) 1
99X
/Lio
n 4
dr/W
agon
23 6
7
11
10
5
Cur
rent
Des
ign
Con
trol
s
Det
ectio
n
Veh
icle
gen
eral
dur
abili
tyte
st v
eh.
T
-118
T
-109
T
-301
Veh
icle
gen
eral
dur
abili
tyte
stin
g- a
s ab
ove
Phy
sica
l and
Che
m L
abte
st-
Rep
ort N
o.12
65
Des
ign
aid
inve
stig
atio
nw
ith n
on-f
unct
ioni
ngsp
ray
head
Dra
win
g ev
alua
tion
of s
pray
hea
d ac
cess
Sys
tem
XS
ubsy
stem
Cur
rent
Des
ign
Con
trol
s
P
reve
ntio
n
16 SA
MP
LE
FM
EA
Num
ber
1
234
Pag
e 1
of
1
Pre
pare
d B
y A
. T
ate
- X
6412
- B
ody
Eng
r
FM
EA
Dat
e (O
rig.)
8X
03
22
(
Rev
.) 8
X 0
7 1
4
– 31 –
21) Action(s) Taken After the action has been implemented, enter a brief descriptionof the actual action and effective date.
22) Action Results After the preventive/corrective action has been identified,estimate and record the resulting severity, occurrence, anddetection rankings. Calculate and record the resulting RPN. Ifno actions are taken, leave the related ranking columns blank.
All revised ratings should be reviewed. If further action isconsidered necessary, repeat the analysis. The focus shouldalways be on continuous improvement.
Follow-Up Actions
The design-responsible engineer is responsible for ensuring thatall actions recommended have been implemented or adequatelyaddressed. The FMEA is a living document and should alwaysreflect the latest design level as well as the latest relevantactions, including those occurring after start of production.
The design-responsible engineer has several means of ensuringthat concerns are identified and that recommended actions areimplemented. They include, but are not limited to the following:
• Ensuring design requirements are achieved,• Reviewing engineering drawings and specifications,• Confirming incorporation in assembly/manufacturing
documentation, and,• Reviewing Process FMEAs and Control Plans.
DESIGN FMEA
– 32 –
POTENTIAL
FAILURE MODE AND EFFECTS ANALYSIS
IN
MANUFACTURING AND ASSEMBLY PROCESSES
(PROCESS FMEA)
PROCESS FMEA
– 33 –
– 34 –
– 35 –
A Process Potential FMEA is an analytical technique used by aManufacturing/Assembly-Responsible Engineer/Team as ameans to ensure that, to the extent possible, potential failuremodes and their associated causes/mechanisms have beenconsidered and addressed. In its most rigorous form, an FMEAis a summary of the team’s thoughts (including an analysis ofitems that could go wrong based on experience) as a process isdeveloped. This systematic approach parallels and formalizesthe mental discipline that an engineer normally goes through inany manufacturing planning process.
The Process Potential FMEA:
• Identifies the process functions and requirements• Identifies potential product and process-related failure
modes,• Assesses the effects of the potential failures on the
customer,• Identifies the potential manufacturing or assembly
process causes and identifies process variables onwhich to focus controls for occurrence reduction ordetection of the failure conditions,
• Identifies process variables on which to focus processcontrols,
• Develops a ranked list of potential failure modes, thusestablishing a priority system for preventive/correctiveaction considerations, and,
• Documents the results of the manufacturing orassembly process.
Customer Defined The definition of “Customer” for a Process FMEA shouldnormally be the “End User.” However, the customer can also bea subsequent or downstream manufacturing or assemblyoperation, a service operation, or government regulations.
.
Team Effort During the initial development of the Process FMEA, theresponsible engineer is expected to directly and actively involverepresentatives from all affected areas. These areas shouldinclude but are not limited to design, assembly, manufacturing,materials, quality, service, and suppliers, as well as the arearesponsible for the next assembly. The Process FMEA shouldbe a catalyst to stimulate the interchange of ideas between theareas affected and thus promote a team approach.
Unless the responsible engineer is experienced with FMEA andteam facilitation, it is helpful to have an experienced FMEAfacilitator assist the team in its activities.
PROCESS FMEA
INTRODUCTION
– 36 –
TABLE 5. PROCESS FMEA
10
Cor
e T
eam
A
. Tat
e B
ody
Eng
rg.,
J. S
mith
-OC
, R. J
ames
-Pro
duct
ion,
J. J
ones
-Mai
nten
ance
Pro
cess
Res
pons
ibili
ty B
ody
Eng
rg.
Key
Dat
e 9
X 0
3 0
1 E
R
9X
08
26
Job
#1
FM
EA
Num
ber
1
450
Pag
e 1
of
1
Pre
pare
d B
y J
. For
d -
X65
21 -
Ass
y O
ps
FM
EA
Dat
e (O
rig.)
9X
05
17
(R
ev.)
9X
11
06
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(PR
OC
ES
S F
ME
A)
Item
F
ront
Doo
r L.
H./H
8HX
-000
-A
Mod
el Y
ears
( S)/
Veh
icle
(s)
199
X/L
ion
4dr
/Wag
on
23 6
75
8
Pro
cess
Fun
ctio
n
R
equi
rem
ents
Man
ual
appl
icat
ion
ofw
ax in
side
doo
r
To
cove
r in
ner
door
, low
ersu
rfac
es a
tm
inim
um w
axth
ickn
ess
tore
tard
cor
rosi
on
Pot
entia
lF
ailu
reM
ode
Insu
ffici
ent
wax
cov
erag
eov
er s
peci
fied
surf
ace
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lea
ding
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ough
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
o
har
dwar
e
C l a s s
S e v 7 7 7 7
O c c u r 8 5 2 8
D e t e c 5 5 5 7
R.
P.
N.
280
175
70 392
S e v 7 7 7
R.
P.
N.
70 35 49
O c c 2 1 1
D e t 5 5 7
▲
▲
▲
▲
Act
ion
Res
ults
▲
Act
ions
Tak
en
Sto
p ad
ded,
spra
yer
chec
ked
on li
ne
Rej
ecte
d du
e to
com
plex
ity o
fdi
ffere
nt d
oors
on s
ame
line
Tem
p an
d pr
ess
limits
wer
ede
term
ined
and
limit
cont
rols
have
bee
nin
stal
led
-co
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=1.
85
Aut
omat
ic s
pray
timer
inst
alle
d -
oper
ator
sta
rts
spra
y, ti
mer
cont
rols
shu
t-of
fco
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=2.
05
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
MF
G E
ngrg
9X 1
0 1
5
Mfg
Eng
rg9X
12
15
Mfg
Eng
rg9X
10
01
Mai
nten
ance
9X 0
9 1
5
1213
14
Cur
rent
Pro
cess
Con
trol
s
Det
ectio
n
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Ope
rato
r in
stru
ctio
ns a
ndlo
t sam
plin
g (1
0 do
ors
/sh
ift)
to c
heck
for
cove
rage
of c
ritic
al a
reas
16
1518
17
1920
21
22
11
P
oten
tial
C
ause
(s)/
Mec
hani
sm(s
)
o
f Fai
lure
Man
ually
inse
rted
spra
y he
ad n
otin
sert
ed fa
ren
ough
Spr
ay h
eads
c
logg
ed -
Vis
cosi
ty to
o
hig
h -
Tem
pera
ture
t
oo lo
w -
Pre
ssur
e
too
low
Spr
ay h
ead
defo
rmed
due
to im
pact
Spr
ay ti
me
insu
ffici
ent
Rec
omm
ende
dA
ctio
n(s)
Add
pos
itive
dept
h st
op to
spra
yer
Aut
omat
esp
rayi
ng
Use
Des
ign
ofE
xper
imen
ts(D
OE
) on
visc
osity
vs.
tem
pera
ture
vs.
pres
sure
Non
e
Inst
all s
pray
timer
9
Cur
rent
Pro
cess
Con
trol
s
Pre
vent
ion
Tes
t spr
ay p
atte
rn a
tst
art-
up a
nd a
fter
idle
perio
ds, a
nd p
reve
ntiv
em
aint
enan
ce p
rogr
am to
clea
n he
ads
Pre
vent
ive
mai
nten
ance
prog
ram
s to
mai
ntai
n he
ads
16
SA
MP
LE
– 37 –
The Process FMEA is a living document and should be initiated:• Before or at the feasibility stage,• Prior to tooling for production, and• Take into account all manufacturing operations, from
individual components to assemblies.
Early review and analysis of new or revised processes ispromoted to anticipate, resolve, or monitor potential processconcerns during the manufacturing planning stages of a newmodel or component program.
The Process FMEA assumes the product as designed will meetthe design intent. Potential failure modes that can occurbecause of a design weakness may be included in a ProcessFMEA. Their effect and avoidance is covered by the DesignFMEA.
The Process FMEA does not rely on product design changes toovercome weaknesses in the process. However, it does takeinto consideration a product’s design characteristics relative tothe planned manufacturing or assembly process to assure that,to the extent possible, the resultant product meets customerneeds and expectations.
DEVELOPMENT OF A PROCESS FMEA
The process-responsible engineer has at his or her disposal anumber of documents that will be useful in preparing theProcess FMEA. The FMEA begins by developing a list of whatthe process is expected to do and what it is expected not to do,i.e., the process intent.
The Process FMEA should begin with a flow chart of the generalprocess. This flow chart should identify the product/processcharacteristics associated with each operation. Identification ofsome product effects from the corresponding Design FMEA,should be included, if available. Copies of the flow chart used inFMEA preparation should accompany the FMEA.
In order to facilitate documentation of the analysis of potentialfailures and their consequences, a Process FMEA form hasbeen developed and is in Appendix G.
1) FMEA Number Enter the FMEA document number, which may be used fortracking.
Note: For an example of items 1-22 see Table 5.
PROCESS FMEA
INTRODUCTION (Continued)
– 38 –
TABLE 5. PROCESS FMEA
10
Cor
e T
eam
A
. Tat
e B
ody
Eng
rg.,
J. S
mith
-OC
, R. J
ames
-Pro
duct
ion,
J. J
ones
-Mai
nten
ance
Pro
cess
Res
pons
ibili
ty B
ody
Eng
rg.
Key
Dat
e 9
X 0
3 0
1 E
R
9X
08
26
Job
#1
FM
EA
Num
ber
1
450
Pag
e 1
of
1
Pre
pare
d B
y J
. For
d -
X65
21 -
Ass
y O
ps
FM
EA
Dat
e (O
rig.)
9X
05
17
(R
ev.)
9X
11
06
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(PR
OC
ES
S F
ME
A)
Item
F
ront
Doo
r L.
H./H
8HX
-000
-A
Mod
el Y
ears
( S)/
Veh
icle
(s)
199
X/L
ion
4dr
/Wag
on
23 6
75
8
Pro
cess
Fun
ctio
n
R
equi
rem
ents
Man
ual
appl
icat
ion
ofw
ax in
side
doo
r
To
cove
r in
ner
door
, low
ersu
rfac
es a
tm
inim
um w
axth
ickn
ess
tore
tard
cor
rosi
on
Pot
entia
lF
ailu
reM
ode
Insu
ffici
ent
wax
cov
erag
eov
er s
peci
fied
surf
ace
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lea
ding
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ough
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
o
har
dwar
e
C l a s s
S e v 7 7 7 7
O c c u r 8 5 2 8
D e t e c 5 5 5 7
R.
P.
N.
280
175
70 392
S e v 7 7 7
R.
P.
N.
70 35 49
O c c 2 1 1
D e t 5 5 7
▲
▲
▲
▲
Act
ion
Res
ults
▲
Act
ions
Tak
en
Sto
p ad
ded,
spra
yer
chec
ked
on li
ne
Rej
ecte
d du
e to
com
plex
ity o
fdi
ffere
nt d
oors
on s
ame
line
Tem
p an
d pr
ess
limits
wer
ede
term
ined
and
limit
cont
rols
have
bee
nin
stal
led
-co
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=1.
85
Aut
omat
ic s
pray
timer
inst
alle
d -
oper
ator
sta
rts
spra
y, ti
mer
cont
rols
shu
t-of
fco
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=2.
05
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
MF
G E
ngrg
9X 1
0 1
5
Mfg
Eng
rg9X
12
15
Mfg
Eng
rg9X
10
01
Mai
nten
ance
9X 0
9 1
5
1213
14
Cur
rent
Pro
cess
Con
trol
s
Det
ectio
n
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Ope
rato
r in
stru
ctio
ns a
ndlo
t sam
plin
g (1
0 do
ors
/sh
ift)
to c
heck
for
cove
rage
of c
ritic
al a
reas
16
1518
17
1920
21
22
11
P
oten
tial
C
ause
(s)/
Mec
hani
sm(s
)
o
f Fai
lure
Man
ually
inse
rted
spra
y he
ad n
otin
sert
ed fa
ren
ough
Spr
ay h
eads
c
logg
ed -
Vis
cosi
ty to
o
hig
h -
Tem
pera
ture
t
oo lo
w -
Pre
ssur
e
too
low
Spr
ay h
ead
defo
rmed
due
to im
pact
Spr
ay ti
me
insu
ffici
ent
Rec
omm
ende
dA
ctio
n(s)
Add
pos
itive
dept
h st
op to
spra
yer
Aut
omat
esp
rayi
ng
Use
Des
ign
ofE
xper
imen
ts(D
OE
) on
visc
osity
vs.
tem
pera
ture
vs.
pres
sure
Non
e
Inst
all s
pray
timer
9
Cur
rent
Pro
cess
Con
trol
s
Pre
vent
ion
Tes
t spr
ay p
atte
rn a
tst
art-
up a
nd a
fter
idle
perio
ds, a
nd p
reve
ntiv
em
aint
enan
ce p
rogr
am to
clea
n he
ads
Pre
vent
ive
mai
nten
ance
prog
ram
s to
mai
ntai
n he
ads
16
SA
MP
LE
– 39 –
2) Item Enter the name and number of the system, subsystem, orcomponent for which the process is being analyzed.
3) Process Responsibility Enter the OEM, department, and group. Also include thesupplier name if known.
4) Prepared By Enter the name, telephone number, and company of theengineer responsible for preparing the FMEA.
5) Model Year(s)/Program(s) Enter the intended model year(s)/program(s) that will use and/orbe affected by the design/process being analyzed (if known).
6) Key Date Enter the initial FMEA due date, which should not exceed thescheduled start of production date.
Note: In the case of a supplier, the initial FMEA due dateshould not exceed the customer required ProductionPart Approval Process (PPAP) submission date.
7) FMEA Date Enter the date the original FMEA was compiled and the latestrevision date.
8) Core Team List the names of the responsible individuals and departmentsthat have the authority to identify and/or perform tasks. (It isrecommended that each team member's name, department,telephone number, addresse, etc., be included on a distributionlist.)
Enter a simple description of the process or operation beinganalyzed (e.g., turning, drilling, tapping, welding, assembling).In addition, it is recommended to record the associatedprocess/operation number for the step being analyzed. Theteam should review applicable performance, material, process,environmental, and safety standards. Indicate as concisely aspossible the purpose of the process or operation beinganalyzed, including information about the design (metrics/measurables) of the system, subsystem, or component. Wherethe process involves numerous operations (e.g., assembling)with different potential modes of failure, it may be desirable tolist the operations as separate elements.
10) Potential Failure Mode Potential failure mode is defined as the manner in which theprocess could potentially fail to meet the process requirementsand/or design intent as described in the process function/requirements column. It is a description of the nonconformanceat that specific operation. It can be a cause associated with apotential failure mode in a subsequent (downstream) operationor an effect associated with a potential failure in a previous(upstream) operation. However, in preparing the FMEA, assumethat the incoming part(s)/material(s) are correct. Exceptions canbe made by the FMEA team where historical data indicatedeficiencies in incoming part quality.
List each potential failure mode for the particular operation interms of a component, subsystem, system, or processcharacteristic. Assume that the failure could occur but may notnecessarily occur. The process engineer/team should be able to
9) Process Function/Requirements
PROCESS FMEA
– 40 –
TABLE 5. PROCESS FMEA
10
Cor
e T
eam
A
. Tat
e B
ody
Eng
rg.,
J. S
mith
-OC
, R. J
ames
-Pro
duct
ion,
J. J
ones
-Mai
nten
ance
Pro
cess
Res
pons
ibili
ty B
ody
Eng
rg.
Key
Dat
e 9
X 0
3 0
1 E
R
9X
08
26
Job
#1
FM
EA
Num
ber
1
450
Pag
e 1
of
1
Pre
pare
d B
y J
. For
d -
X65
21 -
Ass
y O
ps
FM
EA
Dat
e (O
rig.)
9X
05
17
(R
ev.)
9X
11
06
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(PR
OC
ES
S F
ME
A)
Item
F
ront
Doo
r L.
H./H
8HX
-000
-A
Mod
el Y
ears
( S)/
Veh
icle
(s)
199
X/L
ion
4dr
/Wag
on
23 6
75
8
Pro
cess
Fun
ctio
n
R
equi
rem
ents
Man
ual
appl
icat
ion
ofw
ax in
side
doo
r
To
cove
r in
ner
door
, low
ersu
rfac
es a
tm
inim
um w
axth
ickn
ess
tore
tard
cor
rosi
on
Pot
entia
lF
ailu
reM
ode
Insu
ffici
ent
wax
cov
erag
eov
er s
peci
fied
surf
ace
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lea
ding
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ough
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
o
har
dwar
e
C l a s s
S e v 7 7 7 7
O c c u r 8 5 2 8
D e t e c 5 5 5 7
R.
P.
N.
280
175
70 392
S e v 7 7 7
R.
P.
N.
70 35 49
O c c 2 1 1
D e t 5 5 7
▲
▲
▲
▲
Act
ion
Res
ults
▲
Act
ions
Tak
en
Sto
p ad
ded,
spra
yer
chec
ked
on li
ne
Rej
ecte
d du
e to
com
plex
ity o
fdi
ffere
nt d
oors
on s
ame
line
Tem
p an
d pr
ess
limits
wer
ede
term
ined
and
limit
cont
rols
have
bee
nin
stal
led
-co
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=1.
85
Aut
omat
ic s
pray
timer
inst
alle
d -
oper
ator
sta
rts
spra
y, ti
mer
cont
rols
shu
t-of
fco
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=2.
05
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
MF
G E
ngrg
9X 1
0 1
5
Mfg
Eng
rg9X
12
15
Mfg
Eng
rg9X
10
01
Mai
nten
ance
9X 0
9 1
5
1213
14
Cur
rent
Pro
cess
Con
trol
s
Det
ectio
n
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Ope
rato
r in
stru
ctio
ns a
ndlo
t sam
plin
g (1
0 do
ors
/sh
ift)
to c
heck
for
cove
rage
of c
ritic
al a
reas
16
1518
17
1920
21
22
11
P
oten
tial
C
ause
(s)/
Mec
hani
sm(s
)
o
f Fai
lure
Man
ually
inse
rted
spra
y he
ad n
otin
sert
ed fa
ren
ough
Spr
ay h
eads
c
logg
ed -
Vis
cosi
ty to
o
hig
h -
Tem
pera
ture
t
oo lo
w -
Pre
ssur
e
too
low
Spr
ay h
ead
defo
rmed
due
to im
pact
Spr
ay ti
me
insu
ffici
ent
Rec
omm
ende
dA
ctio
n(s)
Add
pos
itive
dept
h st
op to
spra
yer
Aut
omat
esp
rayi
ng
Use
Des
ign
ofE
xper
imen
ts(D
OE
) on
visc
osity
vs.
tem
pera
ture
vs.
pres
sure
Non
e
Inst
all s
pray
timer
9
Cur
rent
Pro
cess
Con
trol
s
Pre
vent
ion
Tes
t spr
ay p
atte
rn a
tst
art-
up a
nd a
fter
idle
perio
ds, a
nd p
reve
ntiv
em
aint
enan
ce p
rogr
am to
clea
n he
ads
Pre
vent
ive
mai
nten
ance
prog
ram
s to
mai
ntai
n he
ads
16
SA
MP
LE
– 41 –
pose and answer the following questions:
• How can the process/part fail to meet requirements?• Regardless of engineering specifications, what would a
customer (end user, subsequent operations, or service)consider objectionable?
Start by comparing similar processes and reviewing customer(end user and subsequent operation) claims relating to similarcomponents. In addition, a knowledge of the design intent isnecessary. Typical failure modes could be but are not limited to:
Bent Burred Hole off-locationCracked Hole too shallow Hole missingHandling damage Dirty Hole too deepSurface too rough Deformed Surface too smoothOpen circuited Short circuited Mis-labeled
NOTE: Potential failure modes should be described in"physical" or technical terms, not as a symptomnoticeable by the customer.
Potential effects of failure are defined as the effects of the failuremode on the customer(s).
Describe the effects of the failure in terms of what the customermight notice or experience, remembering that the customer maybe an internal customer as well as the ultimate end user. Stateclearly if the failure mode could impact safety or causenoncompliance to regulations. The customer(s) in this contextcould be the next operation, subsequent operations orlocations, the dealer, and/or the vehicle owner. Each must beconsidered when assessing the potential effect of a failure.
For the end user, the effects should always be stated in terms ofproduct or system performance, such as:
Noise RoughErratic operation ExcessiveEffort InoperativeUnpleasant odor UnstableOperation impaired DraftIntermittent operation Poor appearanceLeaks Vehicle control impairedRework/Repairs Customer dissatisfactionScrap
If the customer is the next operation or subsequent operation(s)/location(s), the effects should be stated in terms of process/operation performance, such as:
Cannot fasten Does not fitCannot bore/tap Does not connectCannot mount Does not matchCannot face Causes excessive tool wearDamages equipment Endangers operator
12) Severity (S) Severity is the rank associated with the most serious effect for agiven failure mode. Severity is a relative ranking within the
PROCESS FMEA
10) Potential Failure Mode(continued)
11) Potential Effect(s) ofFailure
– 42 –
TABLE 5. PROCESS FMEA
10
Cor
e T
eam
A
. Tat
e B
ody
Eng
rg.,
J. S
mith
-OC
, R. J
ames
-Pro
duct
ion,
J. J
ones
-Mai
nten
ance
Pro
cess
Res
pons
ibili
ty B
ody
Eng
rg.
Key
Dat
e 9
X 0
3 0
1 E
R
9X
08
26
Job
#1
FM
EA
Num
ber
1
450
Pag
e 1
of
1
Pre
pare
d B
y J
. For
d -
X65
21 -
Ass
y O
ps
FM
EA
Dat
e (O
rig.)
9X
05
17
(R
ev.)
9X
11
06
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(PR
OC
ES
S F
ME
A)
Item
F
ront
Doo
r L.
H./H
8HX
-000
-A
Mod
el Y
ears
( S)/
Veh
icle
(s)
199
X/L
ion
4dr
/Wag
on
23 6
75
8
Pro
cess
Fun
ctio
n
R
equi
rem
ents
Man
ual
appl
icat
ion
ofw
ax in
side
doo
r
To
cove
r in
ner
door
, low
ersu
rfac
es a
tm
inim
um w
axth
ickn
ess
tore
tard
cor
rosi
on
Pot
entia
lF
ailu
reM
ode
Insu
ffici
ent
wax
cov
erag
eov
er s
peci
fied
surf
ace
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lea
ding
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ough
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
o
har
dwar
e
C l a s s
S e v 7 7 7 7
O c c u r 8 5 2 8
D e t e c 5 5 5 7
R.
P.
N.
280
175
70 392
S e v 7 7 7
R.
P.
N.
70 35 49
O c c 2 1 1
D e t 5 5 7
▲
▲
▲
▲
Act
ion
Res
ults
▲
Act
ions
Tak
en
Sto
p ad
ded,
spra
yer
chec
ked
on li
ne
Rej
ecte
d du
e to
com
plex
ity o
fdi
ffere
nt d
oors
on s
ame
line
Tem
p an
d pr
ess
limits
wer
ede
term
ined
and
limit
cont
rols
have
bee
nin
stal
led
-co
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=1.
85
Aut
omat
ic s
pray
timer
inst
alle
d -
oper
ator
sta
rts
spra
y, ti
mer
cont
rols
shu
t-of
fco
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=2.
05
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
MF
G E
ngrg
9X 1
0 1
5
Mfg
Eng
rg9X
12
15
Mfg
Eng
rg9X
10
01
Mai
nten
ance
9X 0
9 1
5
1213
14
Cur
rent
Pro
cess
Con
trol
s
Det
ectio
n
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Ope
rato
r in
stru
ctio
ns a
ndlo
t sam
plin
g (1
0 do
ors
/sh
ift)
to c
heck
for
cove
rage
of c
ritic
al a
reas
16
1518
17
1920
21
22
11
P
oten
tial
C
ause
(s)/
Mec
hani
sm(s
)
o
f Fai
lure
Man
ually
inse
rted
spra
y he
ad n
otin
sert
ed fa
ren
ough
Spr
ay h
eads
c
logg
ed -
Vis
cosi
ty to
o
hig
h -
Tem
pera
ture
t
oo lo
w -
Pre
ssur
e
too
low
Spr
ay h
ead
defo
rmed
due
to im
pact
Spr
ay ti
me
insu
ffici
ent
Rec
omm
ende
dA
ctio
n(s)
Add
pos
itive
dept
h st
op to
spra
yer
Aut
omat
esp
rayi
ng
Use
Des
ign
ofE
xper
imen
ts(D
OE
) on
visc
osity
vs.
tem
pera
ture
vs.
pres
sure
Non
e
Inst
all s
pray
timer
9
Cur
rent
Pro
cess
Con
trol
s
Pre
vent
ion
Tes
t spr
ay p
atte
rn a
tst
art-
up a
nd a
fter
idle
perio
ds, a
nd p
reve
ntiv
em
aint
enan
ce p
rogr
am to
clea
n he
ads
Pre
vent
ive
mai
nten
ance
prog
ram
s to
mai
ntai
n he
ads
16
SA
MP
LE
– 43 –
Effect Ranking
Table 6. Suggested PFMEA Severity Evaluation Criteria
Criteria: Severity of EffectThis ranking results when apotential failure mode results in afinal customer and/or amanufacturing/assembly plantdefect. The final customer shouldalways be considered first. If bothoccur, use the higher of the twoseverities.
(Customer Effect) (Manufacturing/ Assembly Effect)
Hazardouswithoutwarning
Very high severity ranking when apotential failure mode affects safevehicle operation and/or involvesnoncompliance with governmentregulation without warning.
Or may endanger operator (machineor assembly) without warning.
10
Hazardouswith warning
9Very high severity ranking when apotential failure mode affects safevehicle operation and/or involvesnoncompliance with governmentregulation with warning.
Or may endanger operator (machineor assembly) with warning.
Very High 8Vehicle/item inoperable (loss ofprimary function).
Or 100% of product may have to bescrapped, or vehicle/item repaired inrepair department with a repair timegreater than one hour.
High 7Vehicle/Item operable but at areduced level of performance.Customer very dissatisfied.
Or product may have to be sortedand a portion (less than 100%)scrapped, or vehicle/item repaired inrepair department with a repair timebetween a half-hour and an hour.
Moderate 6Vehicle/Item operable but Comfort/Convenience item(s) inoperable.Customer dissatisfied.
Or a portion (less than 100%) of theproduct may have to scrapped withno sorting, or vehicle/item repaired inrepair department with a repair timeless than a half-hour.
Low 5Vehicle/Item operable but Comfort/Convenience item(s) operable at areduced level of performance.
Or 100% of product may have to bereworked, or vehicle/item repaired off-line but does not go to repairdepartment.
Very Low 4Fit and Finish/Squeak and Rattle itemdoes not conform. Defect noticed bymost customers (greater than 75%).
Or the product may have to besorted, with no scrap, and a portion(less than 100%) reworked.
Minor 3Fit and Finish/Squeak and Rattle itemdoes not conform. Defect noticed by50% of customers.
Or a portion (less than 100%) of theproduct may have to be reworked,with no scrap, on-line but out-of-sta-tion.
Very Minor 2Fit and Finish/Squeak and Rattle itemdoes not conform. Defect noticed bydiscriminating customers (less than25%).
Or a portion (less than 100%) of theproduct may have to be reworked,with no scrap, on-line but in-station.
None 1No discernible effect. Or slight inconvenience to operation
or operator, or no effect.
Criteria: Severity of EffectThis ranking results when apotential failure mode results in afinal customer and/or amanufacturing/assembly plantdefect. The final customer shouldalways be considered first. If bothoccur, use the higher of the twoseverities.
PROCESS FMEA
– 44 –
TABLE 5. PROCESS FMEA
10
Cor
e T
eam
A
. Tat
e B
ody
Eng
rg.,
J. S
mith
-OC
, R. J
ames
-Pro
duct
ion,
J. J
ones
-Mai
nten
ance
Pro
cess
Res
pons
ibili
ty B
ody
Eng
rg.
Key
Dat
e 9
X 0
3 0
1 E
R
9X
08
26
Job
#1
FM
EA
Num
ber
1
450
Pag
e 1
of
1
Pre
pare
d B
y J
. For
d -
X65
21 -
Ass
y O
ps
FM
EA
Dat
e (O
rig.)
9X
05
17
(R
ev.)
9X
11
06
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(PR
OC
ES
S F
ME
A)
Item
F
ront
Doo
r L.
H./H
8HX
-000
-A
Mod
el Y
ears
( S)/
Veh
icle
(s)
199
X/L
ion
4dr
/Wag
on
23 6
75
8
Pro
cess
Fun
ctio
n
R
equi
rem
ents
Man
ual
appl
icat
ion
ofw
ax in
side
doo
r
To
cove
r in
ner
door
, low
ersu
rfac
es a
tm
inim
um w
axth
ickn
ess
tore
tard
cor
rosi
on
Pot
entia
lF
ailu
reM
ode
Insu
ffici
ent
wax
cov
erag
eov
er s
peci
fied
surf
ace
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lea
ding
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ough
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
o
har
dwar
e
C l a s s
S e v 7 7 7 7
O c c u r 8 5 2 8
D e t e c 5 5 5 7
R.
P.
N.
280
175
70 392
S e v 7 7 7
R.
P.
N.
70 35 49
O c c 2 1 1
D e t 5 5 7
▲
▲
▲
▲
Act
ion
Res
ults
▲
Act
ions
Tak
en
Sto
p ad
ded,
spra
yer
chec
ked
on li
ne
Rej
ecte
d du
e to
com
plex
ity o
fdi
ffere
nt d
oors
on s
ame
line
Tem
p an
d pr
ess
limits
wer
ede
term
ined
and
limit
cont
rols
have
bee
nin
stal
led
-co
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=1.
85
Aut
omat
ic s
pray
timer
inst
alle
d -
oper
ator
sta
rts
spra
y, ti
mer
cont
rols
shu
t-of
fco
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=2.
05
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
MF
G E
ngrg
9X 1
0 1
5
Mfg
Eng
rg9X
12
15
Mfg
Eng
rg9X
10
01
Mai
nten
ance
9X 0
9 1
5
1213
14
Cur
rent
Pro
cess
Con
trol
s
Det
ectio
n
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Ope
rato
r in
stru
ctio
ns a
ndlo
t sam
plin
g (1
0 do
ors
/sh
ift)
to c
heck
for
cove
rage
of c
ritic
al a
reas
16
1518
17
1920
21
22
11
P
oten
tial
C
ause
(s)/
Mec
hani
sm(s
)
o
f Fai
lure
Man
ually
inse
rted
spra
y he
ad n
otin
sert
ed fa
ren
ough
Spr
ay h
eads
c
logg
ed -
Vis
cosi
ty to
o
hig
h -
Tem
pera
ture
t
oo lo
w -
Pre
ssur
e
too
low
Spr
ay h
ead
defo
rmed
due
to im
pact
Spr
ay ti
me
insu
ffici
ent
Rec
omm
ende
dA
ctio
n(s)
Add
pos
itive
dept
h st
op to
spra
yer
Aut
omat
esp
rayi
ng
Use
Des
ign
ofE
xper
imen
ts(D
OE
) on
visc
osity
vs.
tem
pera
ture
vs.
pres
sure
Non
e
Inst
all s
pray
timer
9
Cur
rent
Pro
cess
Con
trol
s
Pre
vent
ion
Tes
t spr
ay p
atte
rn a
tst
art-
up a
nd a
fter
idle
perio
ds, a
nd p
reve
ntiv
em
aint
enan
ce p
rogr
am to
clea
n he
ads
Pre
vent
ive
mai
nten
ance
prog
ram
s to
mai
ntai
n he
ads
16
SA
MP
LE
– 45 –
scope of the individual FMEA. A reduction in severity rankingindex can be effected through a design change to system,subsystem or component, or a redesign of the process.
If the customer affected by a failure mode is the manufacturingor assembly plant or the product user, assessing the severitymay lie outside the immediate process engineer’s/team’s field ofexperience or knowledge. In these cases, the Design FMEA,design engineer, and/or subsequent manufacturing or assemblyplant process engineer, should be consulted.
Suggested Evaluation CriteriaThe team should agree on an evaluation criteria and rankingsystem, that is consistent, even if modified for individualprocess analysis. (See Table 6)
Severity should be estimated using Table 6 as a guideline:
NOTE: It is not recommended to modify criteria for rankingvalues of 9 and 10. Failure modes with a rank ofseverity 1 should not be analyzed further.
13) Classification This column may be used to classify any special product orprocess characteristics (e.g., critical, key, major, significant) forcomponents, subsystems, or systems that may requireadditional process controls.
This column may also be used to highlight high priority failuremodes for engineering assessment.
If a classification is identified in the Process FMEA, notify thedesign responsible engineer since this may affect theengineering documents concerning control item identification.
Special product or process characteristic symbols and theirusage is directed by specific company policy and is notstandardized in this document.
Potential cause of failure is defined as how the failure couldoccur, described in terms of something that can be corrected orcan be controlled.
List, to the extent possible, every failure cause assignable toeach potential failure mode. If a cause is exclusive to the failuremode, i.e., if correcting the cause has a direct impact on thefailure mode, then this portion of the FMEA thought process iscompleted. Many causes, however, are not mutually exclusive,and to correct or control the cause, a design of experiments, forexample, may be considered to determine which root causesare the major contributors and which can be most easilycontrolled. The causes should be described so that remedialefforts can be aimed at those causes which are pertinent.Typical failure causes may include, but are not limited to:
Improper torque - over, underImproper weld - current, time, pressureInaccurate gaugingImproper heat treat - time, temperature
14) Potential Cause(s)/Mechanism(s) of Failure
12) Severity (S) (continued)
– 46 –
TABLE 5. PROCESS FMEA
10
Cor
e T
eam
A
. Tat
e B
ody
Eng
rg.,
J. S
mith
-OC
, R. J
ames
-Pro
duct
ion,
J. J
ones
-Mai
nten
ance
Pro
cess
Res
pons
ibili
ty B
ody
Eng
rg.
Key
Dat
e 9
X 0
3 0
1 E
R
9X
08
26
Job
#1
FM
EA
Num
ber
1
450
Pag
e 1
of
1
Pre
pare
d B
y J
. For
d -
X65
21 -
Ass
y O
ps
FM
EA
Dat
e (O
rig.)
9X
05
17
(R
ev.)
9X
11
06
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(PR
OC
ES
S F
ME
A)
Item
F
ront
Doo
r L.
H./H
8HX
-000
-A
Mod
el Y
ears
( S)/
Veh
icle
(s)
199
X/L
ion
4dr
/Wag
on
23 6
75
8
Pro
cess
Fun
ctio
n
R
equi
rem
ents
Man
ual
appl
icat
ion
ofw
ax in
side
doo
r
To
cove
r in
ner
door
, low
ersu
rfac
es a
tm
inim
um w
axth
ickn
ess
tore
tard
cor
rosi
on
Pot
entia
lF
ailu
reM
ode
Insu
ffici
ent
wax
cov
erag
eov
er s
peci
fied
surf
ace
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lea
ding
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ough
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
o
har
dwar
e
C l a s s
S e v 7 7 7 7
O c c u r 8 5 2 8
D e t e c 5 5 5 7
R.
P.
N.
280
175
70 392
S e v 7 7 7
R.
P.
N.
70 35 49
O c c 2 1 1
D e t 5 5 7
▲
▲
▲
▲
Act
ion
Res
ults
▲
Act
ions
Tak
en
Sto
p ad
ded,
spra
yer
chec
ked
on li
ne
Rej
ecte
d du
e to
com
plex
ity o
fdi
ffere
nt d
oors
on s
ame
line
Tem
p an
d pr
ess
limits
wer
ede
term
ined
and
limit
cont
rols
have
bee
nin
stal
led
-co
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=1.
85
Aut
omat
ic s
pray
timer
inst
alle
d -
oper
ator
sta
rts
spra
y, ti
mer
cont
rols
shu
t-of
fco
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=2.
05
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
MF
G E
ngrg
9X 1
0 1
5
Mfg
Eng
rg9X
12
15
Mfg
Eng
rg9X
10
01
Mai
nten
ance
9X 0
9 1
5
1213
14
Cur
rent
Pro
cess
Con
trol
s
Det
ectio
n
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Ope
rato
r in
stru
ctio
ns a
ndlo
t sam
plin
g (1
0 do
ors
/sh
ift)
to c
heck
for
cove
rage
of c
ritic
al a
reas
16
1518
17
1920
21
22
11
P
oten
tial
C
ause
(s)/
Mec
hani
sm(s
)
o
f Fai
lure
Man
ually
inse
rted
spra
y he
ad n
otin
sert
ed fa
ren
ough
Spr
ay h
eads
c
logg
ed -
Vis
cosi
ty to
o
hig
h -
Tem
pera
ture
t
oo lo
w -
Pre
ssur
e
too
low
Spr
ay h
ead
defo
rmed
due
to im
pact
Spr
ay ti
me
insu
ffici
ent
Rec
omm
ende
dA
ctio
n(s)
Add
pos
itive
dept
h st
op to
spra
yer
Aut
omat
esp
rayi
ng
Use
Des
ign
ofE
xper
imen
ts(D
OE
) on
visc
osity
vs.
tem
pera
ture
vs.
pres
sure
Non
e
Inst
all s
pray
timer
9
Cur
rent
Pro
cess
Con
trol
s
Pre
vent
ion
Tes
t spr
ay p
atte
rn a
tst
art-
up a
nd a
fter
idle
perio
ds, a
nd p
reve
ntiv
em
aint
enan
ce p
rogr
am to
clea
n he
ads
Pre
vent
ive
mai
nten
ance
prog
ram
s to
mai
ntai
n he
ads
16
SA
MP
LE
– 47 –
Inadequate gating/ventingInadequate or no lubricationPart missing or mislocatedWorn locatorWorn toolChip on locatorBroken toolImproper machine setupImproper programming
Only specific errors or malfunctions (e.g., operator fails to installseal) should be listed; ambiguous phrases (e.g., operator error,machine malfunction) should not be used.
15) Occurrence (O) Occurrence is the likelihood that a specific cause/mechanism offailure will occur. The likelihood of occurrence ranking numberhas a relative meaning rather than an absolute value. Preventingor controlling the causes/mechanisms of failure through adesign or process change is the only way a reduction in theoccurrence ranking can be effected.
Estimate the likelihood of occurrence of potential failure cause/mechanism on a 1 to 10 scale.
A consistent occurrence ranking system should be used toensure continuity. The occurrence ranking number is a relativerating within the scope of the FMEA and may not reflect theactual likelihood of occurrence.
The “Possible Failure Rates” are based on the number offailures that are anticipated during the process execution. Ifstatistical data are available from a similar process, the datashould be used to determine the occurrence ranking. In all othercases, a subjective assessment can be made by using the worddescriptions in the left column of the table, along with anyhistorical data available for similar processes.
Suggested Evaluation CriteriaThe team should agree on an evaluation criteria and rankingsystem that is consistent, even if modified for individual processanalysis. (See Table 7)
Occurrence should be estimated using Table 7 as a guideline:
NOTE: The ranking value of 1 is reserved for “Remote:failure is Unlikely”.
PROCESS FMEA
14) Potential Cause(s)/Mechanism(s) of Failure(continued)
TABLE 5. PROCESS FMEA
– 48 –
10
Cor
e T
eam
A
. Tat
e B
ody
Eng
rg.,
J. S
mith
-OC
, R. J
ames
-Pro
duct
ion,
J. J
ones
-Mai
nten
ance
Pro
cess
Res
pons
ibili
ty B
ody
Eng
rg.
Key
Dat
e 9
X 0
3 0
1 E
R
9X
08
26
Job
#1
FM
EA
Num
ber
1
450
Pag
e 1
of
1
Pre
pare
d B
y J
. For
d -
X65
21 -
Ass
y O
ps
FM
EA
Dat
e (O
rig.)
9X
05
17
(R
ev.)
9X
11
06
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(PR
OC
ES
S F
ME
A)
Item
F
ront
Doo
r L.
H./H
8HX
-000
-A
Mod
el Y
ears
( S)/
Veh
icle
(s)
199
X/L
ion
4dr
/Wag
on
23 6
75
8
Pro
cess
Fun
ctio
n
R
equi
rem
ents
Man
ual
appl
icat
ion
ofw
ax in
side
doo
r
To
cove
r in
ner
door
, low
ersu
rfac
es a
tm
inim
um w
axth
ickn
ess
tore
tard
cor
rosi
on
Pot
entia
lF
ailu
reM
ode
Insu
ffici
ent
wax
cov
erag
eov
er s
peci
fied
surf
ace
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lea
ding
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ough
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
o
har
dwar
e
C l a s s
S e v 7 7 7 7
O c c u r 8 5 2 8
D e t e c 5 5 5 7
R.
P.
N.
280
175
70 392
S e v 7 7 7
R.
P.
N.
70 35 49
O c c 2 1 1
D e t 5 5 7
▲
▲
▲
▲
Act
ion
Res
ults
▲
Act
ions
Tak
en
Sto
p ad
ded,
spra
yer
chec
ked
on li
ne
Rej
ecte
d du
e to
com
plex
ity o
fdi
ffere
nt d
oors
on s
ame
line
Tem
p an
d pr
ess
limits
wer
ede
term
ined
and
limit
cont
rols
have
bee
nin
stal
led
-co
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=1.
85
Aut
omat
ic s
pray
timer
inst
alle
d -
oper
ator
sta
rts
spra
y, ti
mer
cont
rols
shu
t-of
fco
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=2.
05
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
MF
G E
ngrg
9X 1
0 1
5
Mfg
Eng
rg9X
12
15
Mfg
Eng
rg9X
10
01
Mai
nten
ance
9X 0
9 1
5
1213
14
Cur
rent
Pro
cess
Con
trol
s
Det
ectio
n
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Ope
rato
r in
stru
ctio
ns a
ndlo
t sam
plin
g (1
0 do
ors
/sh
ift)
to c
heck
for
cove
rage
of c
ritic
al a
reas
16
1518
17
1920
21
22
11
P
oten
tial
C
ause
(s)/
Mec
hani
sm(s
)
o
f Fai
lure
Man
ually
inse
rted
spra
y he
ad n
otin
sert
ed fa
ren
ough
Spr
ay h
eads
c
logg
ed -
Vis
cosi
ty to
o
hig
h -
Tem
pera
ture
t
oo lo
w -
Pre
ssur
e
too
low
Spr
ay h
ead
defo
rmed
due
to im
pact
Spr
ay ti
me
insu
ffici
ent
Rec
omm
ende
dA
ctio
n(s)
Add
pos
itive
dept
h st
op to
spra
yer
Aut
omat
esp
rayi
ng
Use
Des
ign
ofE
xper
imen
ts(D
OE
) on
visc
osity
vs.
tem
pera
ture
vs.
pres
sure
Non
e
Inst
all s
pray
timer
9
Cur
rent
Pro
cess
Con
trol
s
Pre
vent
ion
Tes
t spr
ay p
atte
rn a
tst
art-
up a
nd a
fter
idle
perio
ds, a
nd p
reve
ntiv
em
aint
enan
ce p
rogr
am to
clea
n he
ads
Pre
vent
ive
mai
nten
ance
prog
ram
s to
mai
ntai
n he
ads
16
SA
MP
LE
– 49 –
*For associated Ppk calculations and values, see Appendix I.
Current Process Controls are descriptions of the controls thateither prevent to the extent possible the failure mode or cause/mechanism of failure from occurring, or detect the failure modeor cause/mechanism of failure should it occur. These controlscan be process controls such as error/mistake proofing,statistical process control (SPC), or can be post-processevaluation. The evaluation may occur at the subject operationor at subsequent operations.
There are two types of Process Controls to consider:
Prevention: Prevent the cause/mechanism of failure orthe failure mode from occurring, or reducetheir rate or occurrence,
Detection: Detect the cause/mechanism of failure or thefailure mode, and lead to correctiveaction(s).
The preferred approach is to first use prevention controls, ifpossible. The initial occurrence rankings will be affected by theprevention controls provided they are integrated as part of theprocess intent. The initial rankings for detection will be basedon process controls that either detect the cause/mechanism offailure, or detect the failure mode.
The Process FMEA form in this manual has two columns for theprocess controls (i.e., separate columns for Prevention Controlsand Detection Controls) to assist the team in clearlydistinguishing between these two types of process controls.This allows for a quick visual determination that both types ofprocess controls have been considered. Use of this two-column form is the preferred approach.
PROCESS FMEA
RankingLikely Failure Rates*
10
9
8
7
6
5
4
3
2
1
> 100 per thousand pieces
50 per thousand pieces
20 per thousand pieces
10 per thousand pieces
5 per thousand pieces
2 per thousand pieces
1 per thousand pieces
0.5 per thousand pieces
0.1 per thousand pieces
< 0.01 per thousand pieces
Very High: Persistent Failures
High: Frequent Failures
Moderate: Occasional Failures
Low: Relatively Few Failures
Remote: Failure is Unlikely
Probability
Table 7. Suggested PFMEA Occurrence Evaluation Criteria
16) Current ProcessControls
TABLE 5. PROCESS FMEA
– 50 –
10
Cor
e T
eam
A
. Tat
e B
ody
Eng
rg.,
J. S
mith
-OC
, R. J
ames
-Pro
duct
ion,
J. J
ones
-Mai
nten
ance
Pro
cess
Res
pons
ibili
ty B
ody
Eng
rg.
Key
Dat
e 9
X 0
3 0
1 E
R
9X
08
26
Job
#1
FM
EA
Num
ber
1
450
Pag
e 1
of
1
Pre
pare
d B
y J
. For
d -
X65
21 -
Ass
y O
ps
FM
EA
Dat
e (O
rig.)
9X
05
17
(R
ev.)
9X
11
06
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(PR
OC
ES
S F
ME
A)
Item
F
ront
Doo
r L.
H./H
8HX
-000
-A
Mod
el Y
ears
( S)/
Veh
icle
(s)
199
X/L
ion
4dr
/Wag
on
23 6
75
8
Pro
cess
Fun
ctio
n
R
equi
rem
ents
Man
ual
appl
icat
ion
ofw
ax in
side
doo
r
To
cove
r in
ner
door
, low
ersu
rfac
es a
tm
inim
um w
axth
ickn
ess
tore
tard
cor
rosi
on
Pot
entia
lF
ailu
reM
ode
Insu
ffici
ent
wax
cov
erag
eov
er s
peci
fied
surf
ace
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lea
ding
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ough
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
o
har
dwar
e
C l a s s
S e v 7 7 7 7
O c c u r 8 5 2 8
D e t e c 5 5 5 7
R.
P.
N.
280
175
70 392
S e v 7 7 7
R.
P.
N.
70 35 49
O c c 2 1 1
D e t 5 5 7
▲
▲
▲
▲
Act
ion
Res
ults
▲
Act
ions
Tak
en
Sto
p ad
ded,
spra
yer
chec
ked
on li
ne
Rej
ecte
d du
e to
com
plex
ity o
fdi
ffere
nt d
oors
on s
ame
line
Tem
p an
d pr
ess
limits
wer
ede
term
ined
and
limit
cont
rols
have
bee
nin
stal
led
-co
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=1.
85
Aut
omat
ic s
pray
timer
inst
alle
d -
oper
ator
sta
rts
spra
y, ti
mer
cont
rols
shu
t-of
fco
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=2.
05
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
MF
G E
ngrg
9X 1
0 1
5
Mfg
Eng
rg9X
12
15
Mfg
Eng
rg9X
10
01
Mai
nten
ance
9X 0
9 1
5
1213
14
Cur
rent
Pro
cess
Con
trol
s
Det
ectio
n
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Ope
rato
r in
stru
ctio
ns a
ndlo
t sam
plin
g (1
0 do
ors
/sh
ift)
to c
heck
for
cove
rage
of c
ritic
al a
reas
16
1518
17
1920
21
22
11
P
oten
tial
C
ause
(s)/
Mec
hani
sm(s
)
o
f Fai
lure
Man
ually
inse
rted
spra
y he
ad n
otin
sert
ed fa
ren
ough
Spr
ay h
eads
c
logg
ed -
Vis
cosi
ty to
o
hig
h -
Tem
pera
ture
t
oo lo
w -
Pre
ssur
e
too
low
Spr
ay h
ead
defo
rmed
due
to im
pact
Spr
ay ti
me
insu
ffici
ent
Rec
omm
ende
dA
ctio
n(s)
Add
pos
itive
dept
h st
op to
spra
yer
Aut
omat
esp
rayi
ng
Use
Des
ign
ofE
xper
imen
ts(D
OE
) on
visc
osity
vs.
tem
pera
ture
vs.
pres
sure
Non
e
Inst
all s
pray
timer
9
Cur
rent
Pro
cess
Con
trol
s
Pre
vent
ion
Tes
t spr
ay p
atte
rn a
tst
art-
up a
nd a
fter
idle
perio
ds, a
nd p
reve
ntiv
em
aint
enan
ce p
rogr
am to
clea
n he
ads
Pre
vent
ive
mai
nten
ance
prog
ram
s to
mai
ntai
n he
ads
16
SA
MP
LE
– 51 –
If a one-column (for process controls) form is used, then thefollowing prefixes should be used. For prevention controls,place a 'P' before each prevention control listed. For detectioncontrols, place a 'D' before each detection control listed.
Once the process controls have been identified, review allprevention controls to determine if any occurrence rankingsneed to be revised.
17) Detection (D) Detection is the rank associated with the best detection controllisted in the process control column. Detection is a relativeranking, within the scope of the individual FMEA. In order toachieve a lower ranking, generally the planned process controlhas to be improved.
Assume the failure has occurred and then assess thecapabilities of all "Current Process Controls" to preventshipment of the part having this failure mode or defect. Do notautomatically presume that the detection ranking is low becausethe occurrence is low (e.g., when control charts are used), butdo assess the ability of the process controls to detect lowfrequency failure modes or prevent them from going further inthe process.
Random quality checks are unlikely to detect the existence of anisolated defect and should not influence the detection ranking.Sampling done on a statistical basis is a valid detection control.
PROCESS FMEA
16) Current ProcessControls (continued)
TABLE 5. PROCESS FMEA
– 52 –
10
Cor
e T
eam
A
. Tat
e B
ody
Eng
rg.,
J. S
mith
-OC
, R. J
ames
-Pro
duct
ion,
J. J
ones
-Mai
nten
ance
Pro
cess
Res
pons
ibili
ty B
ody
Eng
rg.
Key
Dat
e 9
X 0
3 0
1 E
R
9X
08
26
Job
#1
FM
EA
Num
ber
1
450
Pag
e 1
of
1
Pre
pare
d B
y J
. For
d -
X65
21 -
Ass
y O
ps
FM
EA
Dat
e (O
rig.)
9X
05
17
(R
ev.)
9X
11
06
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(PR
OC
ES
S F
ME
A)
Item
F
ront
Doo
r L.
H./H
8HX
-000
-A
Mod
el Y
ears
( S)/
Veh
icle
(s)
199
X/L
ion
4dr
/Wag
on
23 6
75
8
Pro
cess
Fun
ctio
n
R
equi
rem
ents
Man
ual
appl
icat
ion
ofw
ax in
side
doo
r
To
cove
r in
ner
door
, low
ersu
rfac
es a
tm
inim
um w
axth
ickn
ess
tore
tard
cor
rosi
on
Pot
entia
lF
ailu
reM
ode
Insu
ffici
ent
wax
cov
erag
eov
er s
peci
fied
surf
ace
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lea
ding
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ough
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
o
har
dwar
e
C l a s s
S e v 7 7 7 7
O c c u r 8 5 2 8
D e t e c 5 5 5 7
R.
P.
N.
280
175
70 392
S e v 7 7 7
R.
P.
N.
70 35 49
O c c 2 1 1
D e t 5 5 7
▲
▲
▲
▲
Act
ion
Res
ults
▲
Act
ions
Tak
en
Sto
p ad
ded,
spra
yer
chec
ked
on li
ne
Rej
ecte
d du
e to
com
plex
ity o
fdi
ffere
nt d
oors
on s
ame
line
Tem
p an
d pr
ess
limits
wer
ede
term
ined
and
limit
cont
rols
have
bee
nin
stal
led
-co
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=1.
85
Aut
omat
ic s
pray
timer
inst
alle
d -
oper
ator
sta
rts
spra
y, ti
mer
cont
rols
shu
t-of
fco
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=2.
05
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
MF
G E
ngrg
9X 1
0 1
5
Mfg
Eng
rg9X
12
15
Mfg
Eng
rg9X
10
01
Mai
nten
ance
9X 0
9 1
5
1213
14
Cur
rent
Pro
cess
Con
trol
s
Det
ectio
n
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Ope
rato
r in
stru
ctio
ns a
ndlo
t sam
plin
g (1
0 do
ors
/sh
ift)
to c
heck
for
cove
rage
of c
ritic
al a
reas
16
1518
17
1920
21
22
11
P
oten
tial
C
ause
(s)/
Mec
hani
sm(s
)
o
f Fai
lure
Man
ually
inse
rted
spra
y he
ad n
otin
sert
ed fa
ren
ough
Spr
ay h
eads
c
logg
ed -
Vis
cosi
ty to
o
hig
h -
Tem
pera
ture
t
oo lo
w -
Pre
ssur
e
too
low
Spr
ay h
ead
defo
rmed
due
to im
pact
Spr
ay ti
me
insu
ffici
ent
Rec
omm
ende
dA
ctio
n(s)
Add
pos
itive
dept
h st
op to
spra
yer
Aut
omat
esp
rayi
ng
Use
Des
ign
ofE
xper
imen
ts(D
OE
) on
visc
osity
vs.
tem
pera
ture
vs.
pres
sure
Non
e
Inst
all s
pray
timer
9
Cur
rent
Pro
cess
Con
trol
s
Pre
vent
ion
Tes
t spr
ay p
atte
rn a
tst
art-
up a
nd a
fter
idle
perio
ds, a
nd p
reve
ntiv
em
aint
enan
ce p
rogr
am to
clea
n he
ads
Pre
vent
ive
mai
nten
ance
prog
ram
s to
mai
ntai
n he
ads
16
SA
MP
LE
– 53 –
Suggested Evaluation CriteriaThe team should agree on an evaluation criteria and rankingsystem that is consistent, even if modified for individualproduct analysis. (See Table 8.)
Detection should be estimated using Table 8 as a guideline.
NOTE: The ranking value of 1 is reserved for “Certain toDetect.
PROCESS FMEA
17) Detection (D) (continued)
TABLE 8. Suggested PFMEA Detection Evaluation CriteriaDetection Criteria Ranking
A B C
InspectionTypes
Suggested Range of Detection Methods
AlmostImpossible
Absolute certainty of non-detection.
Cannot detect or is not checked. 10
VeryRemote
Controls will probably notdetect.
X Control is achieved with indirect or randomchecks only.
9
Remote Controls have poor chanceof detection.
X Control is achieved with visual inspection only. 8
Very Low Controls have poor chanceof detection.
X Control is achieved with double visual inspectiononly.
7
Low Controls may detect. X Control is achieved with charting methods, suchas SPC {Statistical Process Control}.
6X
Moderate Controls may detect. Control is based on variable gauging after partshave left the station, or Go/No Go gaugingperformed on 100% of the parts after parts haveleft the station.
5X
ModeratelyHigh
Controls have a goodchance to detect.
Error detection in subsequent operations, ORgauging performed on setup and first-piececheck (for set-up causes only).
4XX
High Controls have a goodchance to detect.
Error detection in-station, or error detection insubsequent operations by multiple layers ofacceptance: supply, select, install, verify. Cannotaccept discrepant part.
3XX
Very High Controls almost certain todetect.
Error detection in-station (automatic gauging withautomatic stop feature). Cannot pass discrepantpart.
2XX
Very High Controls certain to detect. Discrepant parts cannot be made because itemhas been error-proofed by process/productdesign.
1X
Inspection Types:A. Error-proofedB. GaugingC. Manual Inspection
X
18) Risk Priority Number (RPN) The risk priority number is the product of the severity (S), occur-rence (O), and detection (D) rankings.
(S) x (O) x (D) = RPN
Within the scope of the individual FMEA, this value (between 1and 1000) can be used to rank order the concerns in the pro-cess.
TABLE 5. PROCESS FMEA
– 54 –
10
Cor
e T
eam
A
. Tat
e B
ody
Eng
rg.,
J. S
mith
-OC
, R. J
ames
-Pro
duct
ion,
J. J
ones
-Mai
nten
ance
Pro
cess
Res
pons
ibili
ty B
ody
Eng
rg.
Key
Dat
e 9
X 0
3 0
1 E
R
9X
08
26
Job
#1
FM
EA
Num
ber
1
450
Pag
e 1
of
1
Pre
pare
d B
y J
. For
d -
X65
21 -
Ass
y O
ps
FM
EA
Dat
e (O
rig.)
9X
05
17
(R
ev.)
9X
11
06
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(PR
OC
ES
S F
ME
A)
Item
F
ront
Doo
r L.
H./H
8HX
-000
-A
Mod
el Y
ears
( S)/
Veh
icle
(s)
199
X/L
ion
4dr
/Wag
on
23 6
75
8
Pro
cess
Fun
ctio
n
R
equi
rem
ents
Man
ual
appl
icat
ion
ofw
ax in
side
doo
r
To
cove
r in
ner
door
, low
ersu
rfac
es a
tm
inim
um w
axth
ickn
ess
tore
tard
cor
rosi
on
Pot
entia
lF
ailu
reM
ode
Insu
ffici
ent
wax
cov
erag
eov
er s
peci
fied
surf
ace
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lea
ding
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ough
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
o
har
dwar
e
C l a s s
S e v 7 7 7 7
O c c u r 8 5 2 8
D e t e c 5 5 5 7
R.
P.
N.
280
175
70 392
S e v 7 7 7
R.
P.
N.
70 35 49
O c c 2 1 1
D e t 5 5 7
▲
▲
▲
▲
Act
ion
Res
ults
▲
Act
ions
Tak
en
Sto
p ad
ded,
spra
yer
chec
ked
on li
ne
Rej
ecte
d du
e to
com
plex
ity o
fdi
ffere
nt d
oors
on s
ame
line
Tem
p an
d pr
ess
limits
wer
ede
term
ined
and
limit
cont
rols
have
bee
nin
stal
led
-co
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=1.
85
Aut
omat
ic s
pray
timer
inst
alle
d -
oper
ator
sta
rts
spra
y, ti
mer
cont
rols
shu
t-of
fco
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=2.
05
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
MF
G E
ngrg
9X 1
0 1
5
Mfg
Eng
rg9X
12
15
Mfg
Eng
rg9X
10
01
Mai
nten
ance
9X 0
9 1
5
1213
14
Cur
rent
Pro
cess
Con
trol
s
Det
ectio
n
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Ope
rato
r in
stru
ctio
ns a
ndlo
t sam
plin
g (1
0 do
ors
/sh
ift)
to c
heck
for
cove
rage
of c
ritic
al a
reas
16
1518
17
1920
21
22
11
P
oten
tial
C
ause
(s)/
Mec
hani
sm(s
)
o
f Fai
lure
Man
ually
inse
rted
spra
y he
ad n
otin
sert
ed fa
ren
ough
Spr
ay h
eads
c
logg
ed -
Vis
cosi
ty to
o
hig
h -
Tem
pera
ture
t
oo lo
w -
Pre
ssur
e
too
low
Spr
ay h
ead
defo
rmed
due
to im
pact
Spr
ay ti
me
insu
ffici
ent
Rec
omm
ende
dA
ctio
n(s)
Add
pos
itive
dept
h st
op to
spra
yer
Aut
omat
esp
rayi
ng
Use
Des
ign
ofE
xper
imen
ts(D
OE
) on
visc
osity
vs.
tem
pera
ture
vs.
pres
sure
Non
e
Inst
all s
pray
timer
9
Cur
rent
Pro
cess
Con
trol
s
Pre
vent
ion
Tes
t spr
ay p
atte
rn a
tst
art-
up a
nd a
fter
idle
perio
ds, a
nd p
reve
ntiv
em
aint
enan
ce p
rogr
am to
clea
n he
ads
Pre
vent
ive
mai
nten
ance
prog
ram
s to
mai
ntai
n he
ads
16
SA
MP
LE
19) Recommended Action(s) Engineering assessment for preventive/corrective action shouldbe first directed at high severity, high RPN, and other itemsdesignated by the team. The intent of any recommended actionis to reduce rankings in the following order: severity, occur-rence, and detection.
In general practice, when the severity is 9 or 10, special atten-tion must be given to ensure that the risk is addressed throughexisting design actions/controls or process preventive/correc-tive action(s), regardless of the RPN. In all cases where theeffect of an identified potential failure mode could be a hazardto manufacturing/assembly personnel, preventive/corrective ac-tions should be taken to avoid the failure mode by eliminating orcontrolling the cause(s), or appropriate operator protectionshould be specified.
After special attention has been given to severity rankings of 9or 10, the team then addresses other failure modes, with theintent of reducing severity, then occurrence, and then detection.
Actions such as, but not limited to, the following should beconsidered:
• To reduce the probability of occurrence, process and/ordesign revisions are required. An action-oriented studyof the process using statistical methods could be imple-mented with an ongoing feedback of information to theappropriate operations for continuous improvement anddefect prevention.
• Only a design and/or process revision can bring about areduction in the severity ranking.
• The preferred method to accomplish a reduction in thedetection ranking is the use of error/mistake proofingmethods. Generally, improving detection controls iscostly and ineffective for quality improvements. Increas-ing the frequency of quality controls inspection is not aneffective preventive/corrective action and should onlybe used as a temporary measure since permanent pre-ventive/corrective action is required. In some cases, adesign change to a specific part may be required toassist in the detection. Changes to the current controlsystem may be implemented to increase this probabil-ity.Emphasis must, however, be placed on preventingdefects (i.e., reducing the occurrence) rather thandetecting them. An example would be the use ofstatistical process control and process improvementrather than random quality checks or associatedinspection.
If engineering assessment leads to no recommended actions fora specific failure mode/cause/control combination, indicate thisby entering “None” in this column.
– 55 –
PROCESS FMEA
TABLE 5. PROCESS FMEA
– 56 –
10
Cor
e T
eam
A
. Tat
e B
ody
Eng
rg.,
J. S
mith
-OC
, R. J
ames
-Pro
duct
ion,
J. J
ones
-Mai
nten
ance
Pro
cess
Res
pons
ibili
ty B
ody
Eng
rg.
Key
Dat
e 9
X 0
3 0
1 E
R
9X
08
26
Job
#1
FM
EA
Num
ber
1
450
Pag
e 1
of
1
Pre
pare
d B
y J
. For
d -
X65
21 -
Ass
y O
ps
FM
EA
Dat
e (O
rig.)
9X
05
17
(R
ev.)
9X
11
06
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(PR
OC
ES
S F
ME
A)
Item
F
ront
Doo
r L.
H./H
8HX
-000
-A
Mod
el Y
ears
( S)/
Veh
icle
(s)
199
X/L
ion
4dr
/Wag
on
23 6
75
8
Pro
cess
Fun
ctio
n
R
equi
rem
ents
Man
ual
appl
icat
ion
ofw
ax in
side
doo
r
To
cove
r in
ner
door
, low
ersu
rfac
es a
tm
inim
um w
axth
ickn
ess
tore
tard
cor
rosi
on
Pot
entia
lF
ailu
reM
ode
Insu
ffici
ent
wax
cov
erag
eov
er s
peci
fied
surf
ace
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lea
ding
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ough
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
o
har
dwar
e
C l a s s
S e v 7 7 7 7
O c c u r 8 5 2 8
D e t e c 5 5 5 7
R.
P.
N.
280
175
70 392
S e v 7 7 7
R.
P.
N.
70 35 49
O c c 2 1 1
D e t 5 5 7
▲
▲
▲
▲
Act
ion
Res
ults
▲
Act
ions
Tak
en
Sto
p ad
ded,
spra
yer
chec
ked
on li
ne
Rej
ecte
d du
e to
com
plex
ity o
fdi
ffere
nt d
oors
on s
ame
line
Tem
p an
d pr
ess
limits
wer
ede
term
ined
and
limit
cont
rols
have
bee
nin
stal
led
-co
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=1.
85
Aut
omat
ic s
pray
timer
inst
alle
d -
oper
ator
sta
rts
spra
y, ti
mer
cont
rols
shu
t-of
fco
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=2.
05
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
MF
G E
ngrg
9X 1
0 1
5
Mfg
Eng
rg9X
12
15
Mfg
Eng
rg9X
10
01
Mai
nten
ance
9X 0
9 1
5
1213
14
Cur
rent
Pro
cess
Con
trol
s
Det
ectio
n
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Ope
rato
r in
stru
ctio
ns a
ndlo
t sam
plin
g (1
0 do
ors
/sh
ift)
to c
heck
for
cove
rage
of c
ritic
al a
reas
16
1518
17
1920
21
22
11
P
oten
tial
C
ause
(s)/
Mec
hani
sm(s
)
o
f Fai
lure
Man
ually
inse
rted
spra
y he
ad n
otin
sert
ed fa
ren
ough
Spr
ay h
eads
c
logg
ed -
Vis
cosi
ty to
o
hig
h -
Tem
pera
ture
t
oo lo
w -
Pre
ssur
e
too
low
Spr
ay h
ead
defo
rmed
due
to im
pact
Spr
ay ti
me
insu
ffici
ent
Rec
omm
ende
dA
ctio
n(s)
Add
pos
itive
dept
h st
op to
spra
yer
Aut
omat
esp
rayi
ng
Use
Des
ign
ofE
xper
imen
ts(D
OE
) on
visc
osity
vs.
tem
pera
ture
vs.
pres
sure
Non
e
Inst
all s
pray
timer
9
Cur
rent
Pro
cess
Con
trol
s
Pre
vent
ion
Tes
t spr
ay p
atte
rn a
tst
art-
up a
nd a
fter
idle
perio
ds, a
nd p
reve
ntiv
em
aint
enan
ce p
rogr
am to
clea
n he
ads
Pre
vent
ive
mai
nten
ance
prog
ram
s to
mai
ntai
n he
ads
16
SA
MP
LE
– 57 –
PROCESS FMEA20) Responsibility for the
Recommended Action(s)Enter the individual responsible for the recommended action,and the target completion date.
21) Action(s) Taken After the action has been implemented, enter a brief descriptionof the actual action and effective date.
22) Action Results After the preventive/corrective action has been identified,estimate and record the resulting severity, occurrence, anddetection rankings. Calculate and record the resulting RPN. Ifno actions are taken, leave the related ranking columns blank.
All revised ratings should be reviewed and if further action isconsidered necessary, repeat the analysis. The focus shouldalways be on continuous improvement.
Follow-Up Actions
The process-responsible engineer is responsible for ensuringthat all actions recommended have been implemented oradequately addressed. The FMEA is a living document andshould always reflect the latest design level as well as the latestrelevant actions, including those occurring after the start ofproduction.
The process-responsible engineer has several means ofensuring that concerns are identified and that recommendedactions are implemented. They include, but are not limited tothe following:
• Ensuring that process/product requirements are achieved,• Reviewing engineering drawings, process/product
specifications, and process flow,• Confirming the incorporation of changes in assembly/
manufacturing documentation and,• Reviewing Control Plans and operation instructions.
PROCESS FMEA
– 58 –
– 59 –
APPENDIX ADESIGN FMEA QUALITY OBJECTIVES
Note: Specific Program Requirements take precedence
1. DESIGN IMPROVEMENTS The FMEA drives Design Improvements as the primaryobjective.
2. HIGH RISK FAILURE MODES The FMEA addresses all high risk Failure Modes, as identified bythe FMEA team, with executable Action Plans. All other failuremodes are considered.
3. A/D/V OR DVP & R PLANS The Analysis/Development/Validation (A/D/V), and/or DesignVerification Plan and Report (DVP&R) considers the failuremodes from the FMEA.
4. INTERFACES The FMEA scope includes integration and interface failuremodes in both block diagram and analysis.
5. LESSONS LEARNED The FMEA considers all major “lessons learned” (such as highwarranty, campaigns, etc.) as input to failure modeidentification.
The FMEA identifies appropriate Key Characteristics candidatesas input to the Key Characteristics selection process, ifapplicable due to company policy.
7. TIMING The FMEA is completed during the “Window of Opportunity”where it could most efficiently impact the product design.
8. TEAM The right people participate as part of the FMEA team through-out the analysis, and are adequately trained in FMEA methods.As appropriate, a facilitator should be used.
9. DOCUMENTATION The FMEA document is completely filled out "by the book",including "Action Taken" and new RPN values.
10.TIME USAGE Time spent by the FMEA team as early as possible is an effec-tive and efficient use of time, with a value-added result. Thisassumes Recommended Actions are identified as required andthe actions are implemented.
6. SPECIAL OR KEYCHARACTERISTICS
– 60 –
APPENDIX BPROCESS FMEA QUALITY OBJECTIVES
Note: Specific Program Requirements take precedence.
1. PROCESS IMPROVEMENTS The FMEA drives Process Improvements as the primaryobjective, with an emphasis on Error/Mistake Proofing solutions.
2. HIGH RISK FAILURE MODES The FMEA addresses all high risk Failure Modes, as identified bythe FMEA team, with executable Action Plans. All other failuremodes are considered.
3. CONTROL PLANS The Pre-launch and Production Control Plans consider thefailure modes from the Process FMEA.
4. INTEGRATION The FMEA is integrated and consistent with the Process FlowDiagram and the Process Control Plan. The Process FMEAconsiders the Design FMEA, if available as part of its analysis.
5. LESSONS LEARNED The FMEA considers all major “lessons learned” (such as highwarranty, campaigns, non-conforming product, customercomplaints, etc.) as input to failure mode identification.
The FMEA identifies appropriate Key Characteristics candidatesas input to the Key Characteristics selection process, ifapplicable due to company policy.
7. TIMING The FMEA is completed during the “Window of Opportunity”where it could most efficiently impact the design of product orprocess.
8. TEAM The right people participate as part of the FMEA teamthroughout the analysis, and are adequately trained in FMEAmethods. As appropriate, a facilitator should be used.
9. DOCUMENTATION The FMEA document is completely filled out "by the book",including "Action Taken" and new RPN values.
10.TIME USAGE Time spent by the FMEA team as early as possible is aneffective and efficient use of time, with a value-added result.This assumes Recommended Actions are identified as requiredand the actions are implemented.
6. SPECIAL OR KEYCHARACTERISTICS
– 61 –
APPENDIX CDESIGN FMEA BLOCK DIAGRAM EXAMPLE
FAILURE MODE AND EFFECTS ANALYSIS (FMEA)BLOCK DIAGRAM/ENVIRONMENTAL EXTREMES
SYSTEM NAME: FLASHLIGHTYEAR VEHICLE PLATFORM: 1994 NEW PRODUCTFMEA I.D. NUMBER XXXI10D001
OPERATIONAL ENVIRONMENTAL EXTREMES
TEMPERATURE: CORROSIVE: VIBRATION:SHOCK: FOREIGN MATERIAL: HUMIDITY:FLAMMABILITY: (WHAT COMPONENT(S) ARE NEAR HEAT SOURCE(S)?OTHER:
LETTERS = COMPONENTS = ATTACHED/JOINED ------- = INTERFACING, NOT JOINED = NOT INCLUDED INNUMBERS = ATTACHING METHODS
-20 TO 160 F TEST SCHEDULE B NOT APPLICABLE6 FOOT DROP DUST 0 - 100 % RH
THIS FMEA
The example below is a relational block diagram. Other types of block diagrams may be used by the FMEATeam to clarify the item(s) being considered in their analysis
SWITCHON/OFF
C
BULBASSEMBLY
D
HOUSINGA
PLATEE+
BATTERIESB
SPRINGF-55
441
2
3
ATTACHING METHOD1. SKIP FIT2. RIVETS3. THREAD4. SNAP FIT5. COMPRESSIVE FIT
COMPONENTSA. HOUSINGB. BATTERIES (2 D CELL)C. ON/OFF SWITCHD. BULB ASSEMBLYE. PLATEF. SPRING
APPENDIX DSTANDARD FORM FOR DESIGN FMEA
– 62 –
Item
F
unct
ion
Pot
entia
lF
ailu
reM
ode
Pot
entia
lE
ffect
(s)
ofF
ailu
re
C l a s s
S e v
O c c u r
D e t e c
R.
P.
N.
S e v
R.
P.
N.
O c c
D e t
Act
ion
Res
ults
Rec
omm
ende
dA
ctio
n(s)
Pot
entia
lC
ause
(s)/
Mec
hani
sm(s
)of
Fai
lure
Act
ions
Tak
en
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
Cor
e T
eam
___
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
Des
ign
Res
pons
ibili
ty _
____
____
Key
Dat
e _
____
____
FM
EA
Num
ber
Pag
e
of
Pre
pare
d B
y
FM
EA
Dat
e (O
rig.)
___
____
__
(R
ev.)
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(DE
SIG
N F
ME
A)
____
Com
pone
nt _
__
Mod
el Y
ear(
S)/
Veh
icle
(s)
___
____
____
____
____
__
Cur
rent
Des
ign
Con
trol
s
-
Pre
vent
ion
- D
etec
tion
____
Sys
tem
____
Sub
syst
em
– 63 –
APPENDIX DSTANDARD FORM FOR DESIGN FMEA
Item
Fun
ctio
n
Pot
entia
lF
ailu
reM
ode
Pot
entia
lE
ffect
(s)
ofF
ailu
re
C l a s s
S e v
O c c u r
D e t e c
R.
P.
N.
S e v
R.
P.
N.
O c c
D e t
Act
ion
Res
ults
Rec
omm
ende
dA
ctio
n(s)
Pot
entia
lC
ause
(s)/
Mec
hani
sm(s
)of
Fai
lure
Act
ions
Tak
en
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
Cor
e T
eam
Des
ign
Res
pons
ibili
ty
Key
Dat
e
FM
EA
Num
ber
Pag
e
of
Pre
pare
d B
y
FM
EA
Dat
e (O
rig.)
(
Rev
.)
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(DE
SIG
N F
ME
A)
Com
pone
nt
MO
DE
L Y
EA
RS(S
)/V
ehic
le(s
)
Cur
rent
Des
ign
Con
trol
s
Det
ectio
n
Sys
tem
Sub
syst
em
Cur
rent
Des
ign
Con
trol
s
P
reve
ntio
n
– 64 –
APPENDIX EDESIGN FMEA EXAMPLE
Item
Fun
ctio
n
Fro
nt D
oor
L.H
.H
8HX
-000
0-A
• In
gres
s to
and
eg
ress
from
ve
hicl
e•
Occ
upan
t
prot
ectio
n
from
wea
ther
,
nois
e, a
nd
side
impa
ct
• S
uppo
rt
anch
orag
e fo
r
door
har
dwar
e
incl
udin
g
mirr
or,
hi
nges
, lat
ch
and
win
dow
re
gula
tor
• P
rovi
de p
rope
r
surf
ace
for
ap
pear
ance
ite
ms
- P
aint
and
sof
t trim
Pot
entia
lF
ailu
reM
ode
Cor
rode
din
terio
rlo
wer
doo
rpa
nels
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lead
ing
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ougH
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
or
har
dwar
e
C l a s s
S e v 7 7 7 7 7
O c c u r 6 4 2 5 4
D e t e c 7 7 2 8 4
R.
P.
N.
294
196
28 280
112
S e v 7 7 7 7
R.
P.
N.
28 28 21 7
O c c 2 2 1 1
D e t 2 2 3 1
▲
▲
▲
▲
Act
ion
Res
ults
▲
Rec
omm
ende
dA
ctio
n(s)
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Add
labo
rato
ryac
cele
rate
dco
rros
ion
test
ing
Con
duct
Des
ign
of E
xper
imen
ts(D
OE
) on
wax
thic
knes
s
Non
e
Add
team
eval
uatio
n us
ing
prod
uctio
n sp
ray
equi
pmen
t and
spec
ified
wax
Add
team
eval
uatio
n us
ing
desi
gn a
id b
uck
and
spra
y he
ad
Pot
entia
lC
ause
(s)/
Mec
hani
sm(s
)of
Fai
lure
Upp
er e
dge
ofpr
otec
tive
wax
appl
icat
ion
spec
ified
for
inne
r do
or p
anel
s is
too
low
Insu
ffici
ent w
axth
ickn
ess
spec
ified
Inap
prop
riate
wax
form
ulat
ion
spec
ified
Ent
rapp
ed a
ir pr
even
tsw
ax fr
om e
nter
ing
corn
er/e
dge
acce
ss
Insu
ffici
ent r
oom
betw
een
pane
ls fo
rsp
ray
head
acc
ess\
Act
ions
Tak
en
Bas
ed o
n te
stre
sults
(T
est N
o.14
81)
uppe
red
ge s
pec
rais
ed12
5mm
Tes
t res
ults
(Tes
t No.
148
1)sh
ow s
peci
fied
thic
knes
s is
adeq
uate
. D
OE
show
s 25
%va
riatio
n in
spec
ified
thic
knes
sis
acc
epta
ble.
Bas
ed o
n te
st, 3
addi
tiona
l ven
tho
les
prov
ided
inaf
fect
ed a
reas
Eva
luat
ion
show
edad
equa
te a
cces
s
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
A T
ate-
Bod
yE
ngrg
8X 0
9 3
0
Com
bine
w/te
stfo
r w
ax u
pper
edge
ver
ifica
tion
A T
ate
Bod
y E
ngrg
9X 0
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 1
1 1
5
Bod
y E
ngrg
&A
ssy
Ops
8X 0
9 15
8
9
1213
1416
1518
17
1920
21
22
Cor
e T
eam
T. F
ende
r-C
ar P
rodu
ct D
ev.,
Chi
lder
s-M
anuf
actu
ring,
J. F
ord-
Ass
y O
ps
(D
alto
n, F
rase
r, H
enle
y A
ssem
bly
Pla
nts)
Des
ign
Res
pons
ibili
ty B
ody
Eng
inee
ring
Key
Dat
e 9
X 0
3 0
1 E
R
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(DE
SIG
N F
ME
A)
Com
pone
nt 0
1.03
/Bod
y C
losu
res
MO
DE
L Y
EA
RS(S
)/V
ehic
le(s
) 1
99X
/Lio
n 4
dr/W
agon
23 6
7
11
10
5
Cur
rent
Des
ign
Con
trol
s
Det
ectio
n
Veh
icle
gen
eral
dur
abili
tyte
st v
eh.
T
-118
T
-109
T
-301
Veh
icle
gen
eral
dur
abili
tyte
stin
g- a
s ab
ove
Phy
sica
l and
Che
m L
abte
st-
Rep
ort N
o.12
65
Des
ign
aid
inve
stig
atio
nw
ith n
on-f
unct
ioni
ngsp
ray
head
Dra
win
g ev
alua
tion
of s
pray
hea
d ac
cess
Sys
tem
XS
ubsy
stem
Cur
rent
Des
ign
Con
trol
s
P
reve
ntio
n
16 SA
MP
LE
FM
EA
Num
ber
1
234
Pag
e 1
of
1
Pre
pare
d B
y A
. T
ate
- X
6412
- B
ody
Eng
r
FM
EA
Dat
e (O
rig.)
8X
03
22
(
Rev
.) 8
X 0
7 1
4
Appendix F System FMEA
To help illustrate the meaning of System, Subsystem, and Component FMEA’s, twoexamples have been constructed below in Figure F1 (for Interfaces and Interactions)and in Figure F2 (for Item, Function, and Failure Modes).
EXAMPLE 1: Interfaces and Interactions
Figure F1. Interfaces and Interactions
The FMEA team is responsible for specifying the scope of its respective FMEA’s. The example in FigureF1 shows that the team has specified Subsystems A, B, C, and D along with the surrounding environmentas comprising the System that must be considered while completing the System FMEA.
INTERFACES: SUBSYSTEMS ARE DIRECTLY CONNECTED VIA INTERFACES.
In Figure F1, interfaces between subsystems are shown where Subsystem A touches(connects with) Subsystem B, B touches C, C touches D, A touches D, and B touchesD. The Environment also touches each of the subsystems listed in Figure F1, whichrequires that the ‘Environmental Interfaces’ be considered when completing theFMEA.
NOTE: Each Subsystem FMEA should have its Interfaces included in its respectiveSubsystem FMEA.
INTERACTIONS: A CHANGE IN ONE SUBSYSTEM MIGHT CAUSE A CHANGE IN ANOTHERSUBSYSTEM.
In Figure F1, interactions between subsystems can occur among any of the interfacingsystems (e.g., Subsystem A heats up, resulting in Subsystem D and Subsystem B alsogaining heat through the respective interfaces, as well as Subsystem A giving off heatto the environment). Interactions might also occur among ‘non-contacting’ systems viatransfer through the ‘environment’ (e.g., if the environment is composed of highhumidity and Subsystems A and C are dissimilar metals separated by a non-metalcomposing Subsystem B, Subsystems A and C can still have an electrolytic reactiondue to the moisture from the environment). Thus, interactions among non-contactingsubsystems can be relatively difficult to predict but are important and should beconsidered.
System
Subsystem D
Subsystem A Subsystem CSubsystem B
Environment
– 65 –
– 66 –
EXAMPLE 2: Items, Functions, and Failure Modes
Figure F2 (see next page) describes a method of showing the Items, Functions, and Failure Modes in a‘tree arrangement’ that can assist the team in visualizing the System, Subsystems, and Components.At the System Level, the descriptions will tend to be much more general than for the Subsystems andComponents (Components will usually have the most specific descriptions).
The ‘tree arrangement’ is arranged as follows for the System, Subsystem, and Components:
ITEM
Design Objectives (a statement of design objectives is often helpful)
- FUNCTION 1POTENTIAL FAILURE MODE APOTENTIAL FAILURE MODE Betc.....
- FUNCTION 2POTENTIAL FAILURE MODE APOTENTIAL FAILURE MODE Betc.....
- etc.....
– 67 –
Des
ign
Ob
ject
ives
:1)
min
imum
300
0 ho
urs
of r
idin
gw
itho
ut n
eed
fo
r m
aint
enan
cean
d 1
0,00
0 ho
urs
of r
idin
g fo
rd
esig
n lif
e.2)
ac
co
mm
od
ate
s m
ale
a
du
lts
co
mfo
rta
bly
to
th
e
99
.5th
per
cent
ile3)
... e
tc. .
..
Func
tio
n:–
ease
of u
se
Po
tent
ial F
ailu
re M
od
e(s)
:•
diff
icul
t to
ste
er•
diff
icul
t to
ped
al
Func
tio
n:–
pro
vid
e re
liab
le t
rans
por
tatio
n
Po
tent
ial F
ailu
re M
od
e(s)
:•
chai
n b
reak
s fr
eque
ntly
•Ti
res
req
uire
freq
uent
mai
nten
ance
Func
tio
n:–
pro
vid
e co
mfo
rtab
letr
ansp
orta
tion
Po
tent
ial F
ailu
re M
od
e(s)
:•
seat
ing
pos
ition
is n
otco
mfo
rtab
le
Bic
ycle
Func
tio
n:–
pro
vid
es s
tab
le a
ttac
hmen
t fo
rse
at s
upp
ort
Po
tent
ial F
ailu
re M
od
e(s)
:•
stru
ctur
al fa
ilure
of s
eat
sup
por
t•
exce
ssiv
e d
efle
ctio
n of
sea
tsu
pp
ort
Func
tio
n:–
pro
vid
es p
leas
ing
app
eara
nce
Po
tent
ial F
ailu
re M
od
e(s)
:•
finis
h (s
hine
) det
erio
rate
s•
pai
nt c
hip
s
Fram
e
Sys
tem
Lev
elS
ubsy
stem
Lev
elC
om
po
nent
Lev
el
Han
dle
Bar
Ass
emb
ly
Fron
t W
heel
Ass
emb
ly
Rea
r W
heel
Ass
emb
ly
Sp
rock
et A
ssem
bly
Sea
t A
ssem
bly
Cha
in A
ssem
bly
Func
tio
n:–
pro
vid
es s
truc
tura
l sup
por
t
Po
tent
ial F
ailu
re M
od
e(s)
:•
stru
ctur
al fa
ilure
•ex
cess
ive
def
lect
ion
Func
tio
n:–
pro
vid
es d
imen
sion
al c
ontr
olfo
r co
rrec
t fin
ishe
d fr
ame
geom
etry
Po
tent
ial F
ailu
re M
od
e(s)
:•
leng
th o
f fra
me
mou
ntin
g p
oint
sto
o lo
ng•
leng
th o
f fra
me
mou
ntin
g p
oint
sto
o sh
ort
Func
tio
n:–
sup
por
t fr
ame
asse
mb
lyp
rod
uctio
n m
etho
ds
(wel
din
g)
Po
tent
ial F
ailu
re M
od
e(s)
:
Up
per
Fra
me
Low
er F
ront
Tub
e
Low
er R
ear
Tub
e
Sp
rock
et T
ube
Fig
ure
F2.
Item
s, F
unct
ions
, and
Fai
lure
s
– 68 –
APPENDIX GSTANDARD FORM FOR PROCESS FMEA
Cor
e T
eam
__
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
___
FM
EA
Num
ber
Pag
e
of
Pre
pare
d B
y
FM
EA
Dat
e (O
rig.)
___
____
__
(R
ev.)
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(PR
OC
ES
S F
ME
A)
Item
Mod
el Y
ear(
S)/
Veh
icle
(s)
___
____
____
____
____
____
____
_
Pot
entia
lF
ailu
reM
ode
Pot
entia
lE
ffect
(s)
ofF
ailu
re
C l a s s
S e v
O c c u r
D e t e c
R.
P.
N.
S e v
R.
P.
N.
O c c
D e t
Act
ion
Res
ults
Act
ions
Tak
en
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
Cur
rent
Des
ign
Con
trol
s
-
Pre
vent
ion
- D
etec
tion
Pot
entia
lC
ause
(s)/
Mec
hani
sm(s
)of
Fai
lure
Pro
cess
Fun
ctio
n
Req
uire
men
ts
Pro
cess
Res
pons
ibili
ty _
____
____
_
Key
Dat
e __
____
___
Rec
omm
ende
dA
ctio
n(s)
APPENDIX GSTANDARD FORM FOR PROCESS FMEA
– 69 –
Cor
e T
eam
Pro
cess
Res
pons
ibili
ty
Key
Dat
e
FM
EA
Num
ber
Pag
e
of
Pre
pare
d B
y
FM
EA
Dat
e (O
rig.)
(
Rev
.)
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(PR
OC
ES
S F
ME
A)
Item
Mod
el Y
ears
( S)/
Veh
icle
(s)
Pro
cess
Fun
ctio
n
R
equi
rem
ents
Pot
entia
lF
ailu
reM
ode
Pot
entia
lE
ffect
(s)
ofF
ailu
re
C l a s s
S e v
O c c u r
D e t e c
R.
P.
N.
S e v
R.
P.
N.
O c c
D e t
Act
ion
Res
ults
Act
ions
Tak
en
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
Cur
rent
Pro
cess
Con
trol
s
Det
ectio
n
Pot
entia
lC
ause
(s)/
Mec
hani
sm(s
)of
Fai
lure
Rec
omm
ende
dA
ctio
n(s)
Cur
rent
Pro
cess
Con
trol
s
Pre
vent
ion
– 70 –
APPENDIX HPROCESS FMEA EXAMPLE
10
Cor
e T
eam
A
. Tat
e B
ody
Eng
rg.,
J. S
mith
-OC
, R. J
ames
-Pro
duct
ion,
J. J
ones
-Mai
nten
ance
Pro
cess
Res
pons
ibili
ty B
ody
Eng
rg.
Key
Dat
e 9
X 0
3 0
1 E
R
9X
08
26
Job
#1
FM
EA
Num
ber
1
450
Pag
e 1
of
1
Pre
pare
d B
y J
. For
d -
X65
21 -
Ass
y O
ps
FM
EA
Dat
e (O
rig.)
9X
05
17
(R
ev.)
9X
11
06
1
4
PO
TE
NT
IAL
FA
ILU
RE
MO
DE
AN
D E
FF
EC
TS
AN
ALY
SIS
(PR
OC
ES
S F
ME
A)
Item
F
ront
Doo
r L.
H./H
8HX
-000
-A
Mod
el Y
ears
( S)/
Veh
icle
(s)
199
X/L
ion
4dr
/Wag
on
23 6
75
8
Pro
cess
Fun
ctio
n
R
equi
rem
ents
Man
ual
appl
icat
ion
ofw
ax in
side
doo
r
To
cove
r in
ner
door
, low
ersu
rfac
es a
tm
inim
um w
axth
ickn
ess
tore
tard
cor
rosi
on
Pot
entia
lF
ailu
reM
ode
Insu
ffici
ent
wax
cov
erag
eov
er s
peci
fied
surf
ace
Pot
entia
lE
ffect
(s)
ofF
ailu
re
Det
erio
rate
d lif
e of
door
lea
ding
to:
• U
nsat
isfa
ctor
y
app
eara
nce
due
to
rus
t thr
ough
p
aint
ove
r tim
e•
Impa
ired
func
tion
o
f int
erio
r do
o
har
dwar
e
C l a s s
S e v 7 7 7 7
O c c u r 8 5 2 8
D e t e c 5 5 5 7
R.
P.
N.
280
175
70 392
S e v 7 7 7
R.
P.
N.
70 35 49
O c c 2 1 1
D e t 5 5 7
▲
▲
▲
▲
Act
ion
Res
ults
▲
Act
ions
Tak
en
Sto
p ad
ded,
spra
yer
chec
ked
on li
ne
Rej
ecte
d du
e to
com
plex
ity o
fdi
ffere
nt d
oors
on s
ame
line
Tem
p an
d pr
ess
limits
wer
ede
term
ined
and
limit
cont
rols
have
bee
nin
stal
led
-co
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=1.
85
Aut
omat
ic s
pray
timer
inst
alle
d -
oper
ator
sta
rts
spra
y, ti
mer
cont
rols
shu
t-of
fco
ntro
l cha
rts
show
pro
cess
isin
con
trol
Cpk
=2.
05
Res
pons
ibili
ty&
Tar
get
Com
plet
ion
Dat
e
MF
G E
ngrg
9X 1
0 1
5
Mfg
Eng
rg9X
12
15
Mfg
Eng
rg9X
10
01
Mai
nten
ance
9X 0
9 1
5
1213
14
Cur
rent
Pro
cess
Con
trol
s
Det
ectio
n
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Vis
ual c
heck
eac
h ho
ur-
1/sh
ift fo
r fil
m th
ickn
ess
(dep
th m
eter
) an
dco
vera
ge
Ope
rato
r in
stru
ctio
ns a
ndlo
t sam
plin
g (1
0 do
ors
/sh
ift)
to c
heck
for
cove
rage
of c
ritic
al a
reas
16
1518
17
1920
21
22
11
P
oten
tial
C
ause
(s)/
Mec
hani
sm(s
)
o
f Fai
lure
Man
ually
inse
rted
spra
y he
ad n
otin
sert
ed fa
ren
ough
Spr
ay h
eads
c
logg
ed -
Vis
cosi
ty to
o
hig
h -
Tem
pera
ture
t
oo lo
w -
Pre
ssur
e
too
low
Spr
ay h
ead
defo
rmed
due
to im
pact
Spr
ay ti
me
insu
ffici
ent
Rec
omm
ende
dA
ctio
n(s)
Add
pos
itive
dept
h st
op to
spra
yer
Aut
omat
esp
rayi
ng
Use
Des
ign
ofE
xper
imen
ts(D
OE
) on
visc
osity
vs.
tem
pera
ture
vs.
pres
sure
Non
e
Inst
all s
pray
timer
9
Cur
rent
Pro
cess
Con
trol
s
Pre
vent
ion
Tes
t spr
ay p
atte
rn a
tst
art-
up a
nd a
fter
idle
perio
ds, a
nd p
reve
ntiv
em
aint
enan
ce p
rogr
am to
clea
n he
ads
Pre
vent
ive
mai
nten
ance
prog
ram
s to
mai
ntai
n he
ads
16
SA
MP
LE
ˆ
RankingLikely Failure Rates*
10
9
8
7
6
5
4
3
2
1
> 100 per thousand pieces
50 per thousand pieces
20 per thousand pieces
10 per thousand pieces
5 per thousand pieces
2 per thousand pieces
1 per thousand pieces
0.5 per thousand pieces
0.1 per thousand pieces
< 0.01 per thousand pieces
Very High: Persistent Failures
High: Frequent Failures
Moderate: Occasional Failures
Low: Relatively Few Failures
Remote: Failure is Unlikely
Probability Ppk
< 0.55
≥ 0.55
≥ 0.78
≥ 0.86
≥ 0.94
≥ 1.00
≥ 1.10
≥ 1.20
≥ 1.30
≥ 1.67
– 71 –
APPENDIX ISUGGESTED PFMEA OCCURRENCE EVALUATION
CRITERIA WITH Ppk VALUES
Sample CalculationSample Calculation to determine Ppk value from a likely failure rate of 5 per thousand pieces.
Defect rate = = .
= 0.0025 divided by 2 for out-of-specifications high or low.
Using a "Z" table the associated "Z" value is 2.81 for a tail value of 0.0025.
1. Z =
where:x = AverageSL = Specifications
2. Ppk =
3. Replace using Z
4. Ppk = = = 0.9367 =~ 0.94
Note: The above Ppk values are to be used by the FMEA team as guidance to assist in determining anoccurrence ranking when valid statistical data is available. No other use of the above Ppk valuesis intended.
51000
0.05
SL - xσs
min (SL upper - x, x - SL lower)3σs
Z3
2.813
0.052
ˆ
– 72 –
Glossary
Control Plans The control plan provides the process monitoring and controlmethods that will be used to control characteristics.
Design Intent List of what a given component/subsystem/system is expectedto do or not do.
Design Life The time period (e.g., cycles, time, mileage) for which the designis intended to perform its requirements.
Design Validation/Verification (DV) A program intended to ensure that the design meets itsrequirements.
Design of Experiments (DOE) Methods that identify factors that affect the mean and variationwith minimum testing/experimentation.
Error/Mistake Proofing Each OEM may have its own unique definition for Error/MistakeProofing. Confer with the OEM for the appropriate definition.
Feature A measurable product characteristic (e.g., radius, hardness) or ameasurable process characteristic (e.g., insertion force,temperature).
Pareto A simple tool that can assist problem solving that involvesranking all potential problem areas.
Process The combination of people, machines and equipment, rawmaterials, methods, and environment that produces a givenproduct or service.
Process Change A change in processing concept that could alter the capability ofthe process to meet the design requirements or the durability ofthe product.
Quality Function Deployment (QFD) A structured method in which customer requirements aretranslated into appropriate technical requirements for eachstage of product development and production.
Root Cause The root cause is the reason for the primary non-conformanceand is the item that requires change to achieve permanentpreventive/corrective action.
Special Process Characteristic A special process characteristic (e.g., critical, key, major,significant) is a process characteristic for which variation mustbe controlled to some target value to ensure that variation in aprocess or a special product characteristic is maintained to itstarget value during manufacturing and assembly.
Special Product Characteristic A special product characteristic (e.g., critical, key, major,significant) is a product characteristic for which reasonablyanticipated variation could significantly affect a product’s safetyor compliance with governmental standards or regulations, or islikely to significantly affect customer satisfaction with a product.
Vehicle Campaign Recall of vehicles for rework or safety inspection.
– 73 –
– 74 –
Inside Back Cover
Back Cover