LAB 8-4 POWER CHAIN TROUBLESHOOTING

Student Two

This lab will also have to be done on the old computers.

Lab Checkoff

Requirement	Completed
Fixed computer
Recorded steps
Messed it up again
Answered questions
Cleaned up lab

Objective

The objective of this lab exercise is to develop your electrical troubleshooting skills. After completingv this lab exercise, you will be able to:

• Identify a power issue.
• Repair an electrical problem.
• Describe some common symptoms of electrical problems.

Materials Required

• Operating system: Windows 9x
• Lab workgroup size: 4 students
• Configuration type: simple

Simple Configuration

• 90 Mhz or better Pentium-compatible computer
• 16 MB of RAM
• 540 MB hard drive
• 1 NIC (Network Interface Card)

Additional Devices: None

Lab Setup & Safety Tips

• Always unplug the power cord and properly ground yourself before touching any component inside a computer.
• If students are working in pairs, identify one as Student 1 and the other as Student 2.

ACTIVITY

Troubleshooting a power supply

Student 2

After Student 1 has reconfigured the lab workstation, answer the following questions, and then repair the lab workstation.

1. Are there any error messages? If so, write them down:

2. What is the problem? Be specific.

3. List several possible solutions:

4. Test your theory (solution) and record the results:

5. How did you discover the problem?

6. In the future, what would you do differently to improve your troubleshooting process?

Student 2

The following should be completed while Student 1 is away from the lab workstation.

1. Power off your lab workstation.
2. Unplug the power cord.
3. Remove the case.
4. Reverse the P8 and P9 power connectors.
5. Replace the case.
6. Plug in the power cord.
7. Power on the lab workstation.

Review Questions

Circle True or False.

1. If a power supply’s fan does not spin, one possibility is that the power supply has failed. True / False
2. The P8 and P9 power connectors can be attached to the system board in any order. True / False
3. Hard drive connectors and the system board connector use the same voltage. True / False
4. A common mistake is to attach the hard drive power connector to the system board. True / False
5. What should be the voltage of a power supply’s ground wires?

6. Elliot has just replaced his system board, and now his computer won’t boot. List three possible power-related problems that could be wrong with his system.

Lab Notes

How should I repair a power supply that is shorting?—As a PC technician,

you should never open or attempt to repair the internal working of a power supply.

Your job is to diagnose the problem and replace the power supply, if necessary.

An electrical troubleshooting tip—When troubleshooting electricity, mentally follow the path the electricity follows, starting from the wall outlet and working your way through the entire PC. In this way, it quickly becomes obvious which part of a PC is having a power problem and, more importantly, which device is causing the electrical problem.

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