Chapter 11 Troubleshooting PC Hardware IT Essentials PC

Chapter 11 Troubleshooting PC Hardware IT Essentials: PC Hardware and Software 1

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 2

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 3

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 4

Troubleshooting Tools and Aids (Digital Multimeter) IT Essentials: PC Hardware and Software 5

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 6

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 l • Keyboard/ mouse l • Modular expansion cards l • Most microprocessors l IT Essentials: PC Hardware and Software Power Supply RAM: DIMMs, SIMMs, RIMMs, etc. Floppy and fixed disk drives Motherboard 7

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 8

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. IT Essentials: PC Hardware and Software 9