5. Check the power cord continuity.
6. Replace the AC/DC power adapter.
7. Verify that the power cord from the AC/DC power adapter to the computer is properly connected. See
“Connectors on the rear of the computer” on page 66.
8. Open the cover. See “Opening the cover” on page 68.
9. Check the Power switch/LED assembly connector on the system board. See “System board locations”
on page 68. Reseat the cable from the Power switch/LED assembly to the system board.
10.Replace the power switch/LED assembly.
11.Replace the system board. See “Replacing the system board” on page 72.
Problem determination tips
Due to the variety of hardware and software combinations that can be encountered, use the following
information to assist you in problem determination. If possible, have this information available when
requesting assistance from Service Support and Engineering functions.
• Machine type and model
• Processor or hard disk upgrades
• Failure symptom
– Do diagnostics indicate a failure?
– What, when, where, single, or multiple systems?
– Is the failure repeatable?
– Has this conguration ever worked?
– If it has been working, what changes were made prior to it failing?
– Is this the original reported failure?
• Diagnostics version
– Type and version level
• Hardware conguration
– Print (print screen) conguration currently in use
– BIOS level
• Operating system software
– Type and version level
Notes: To eliminate confusion, identical systems are considered identical only if they:
1. Are the exact machine type and models
2. Have the same BIOS level
3. Have the same adapters/attachments in the same locations
4. Have the same address jumpers/terminators/cabling
5. Have the same software versions and levels
6. Have the same Diagnostic Diskettes (version)
7. Have the same conguration options set in the system
8. Have the same setup for the operating system control les
Comparing the conguration and software set-up between “working and non-working” systems will often
lead to problem resolution.
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