IT Essentials: PC Hardware and Software 1

Chapter 11

Troubleshooting PC

Hardware

IT Essentials: PC Hardware and Software 2

Troubleshooting Basics

•Effective troubleshooting uses techniques to diagnose and fix

computer problems. A series of logical steps speeds up the

troubleshooting process.

IT Essentials: PC Hardware and Software 3

Troubleshooting Tools and Aids

•Every technician should have a good toolset.

•The typical toolset will include items such as: 

•Flat-head screwdriver

•Phillips-head screwdriver

•Nut drivers

•Needle-nose pliers

•Diagonals or crosscut pliers

•Mirror - helps see into very tight spots

•Flashlight

IT Essentials: PC Hardware and Software 4

Troubleshooting Tools and Aids

•The toolset should include a digital

multimeter, which is a measuring device.

•A digital multimeter can measure voltage,

amps, and ohms in both alternating and

direct current.

•A digital multimeter can be used to test

power supplies, DC/AC voltage and polarity,

resistance (Ohms), diodes, continuity,

coaxial cable, fuses, and batteries.

IT Essentials: PC Hardware and Software 5

Troubleshooting Tools and Aids(Digital Multimeter)

IT Essentials: PC Hardware and Software 6

Troubleshooting Tools and Aids

•Loop-back plugs can provide important

diagnostic information while

troubleshooting serial and parallel ports

(printers).

•Loop-back testing works by sending

signals out and verifying if the correct

input is received back.

•Diagnostic information can be gained

from individual pins, ports, controllers,

and printer output.

IT Essentials: PC Hardware and Software 7

Field Replaceable Units

•Devices that can be replaced or added in the field are called

Field Replaceable Units (FRU). FRUs do not require any

soldering and are easy to remove and install.

Common FRUs are:

•Monitors Power Supply

•Keyboard/ mouse RAM: DIMMs, SIMMs, RIMMs, etc.

•Modular expansion cards Floppy and fixed disk drives

•Most microprocessors Motherboard

IT Essentials: PC Hardware and Software 8

Input Devices

•Input devices such as a keyboard, mouse, scanners, and digital

cameras transfer data into the computer. Most input devices are

detected at startup.

•When troubleshooting input devices, always start with the simple

solutions. Check to make sure the device is properly connected.

•After checking the physical connections of the input device, try

rebooting the computer.

•Pay attention to any errors that display during startup.

•The errors will be indicated either as a text error on the video

display or a POST beep code (a keyboard is not properly

connected, the user might get a beep code or a "301 error

message.“)

IT Essentials: PC Hardware and Software 9

SCSI Interface Issues

•SCSI drives require a separate controller from the IDE

controller.

•The SCSI bus operation and the transfer rate are controlled by

adapter settings. If there is a transfer speed mismatch amongst

the SCSI controllers, the drive might have I/O errors.

•As a rule, attach the SCSI controller set to the last SCSI ID,

which is SCSI ID #7. Input/Output errors might result if the SCSI

ID is not set to 7.

•An important consideration with SCSI IDs is, the higher the

SCSI ID, the higher the priority. The actual ID priority is 7, 6, 5, 4,

3, 2, 1, 0, 15, 14, 13, 12, 11, 10, 9, 8.