Checking for power problems
If the computer does not turn on when the power switch is pressed, use the
following procedure to help troubleshoot:
1. Press the power switch to turn on the computer. Check the power indicator
LED next to the power switch.
v If the LED is illuminated (on), the computer power is OK. Attempt to run
the diagnostics. See “Running diagnostics from the disc” on page 46.
v If the LED is not illuminated (off), go to step 2
2. Check the status of the power indicator LED on the AC/DC power adapter.
v If the LED is illuminated (on), go to step 7.
v If the LED is not illuminated (off), go to the next step 3.
3. Verify that the power cord is properly connected to an AC power outlet.
4. Verify that you are using a good AC power outlet. Plug another device into
the outlet or contact the power company or supplier to verify that the outlet is
working correctly .
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 “Locating connectors on the rear of the computer” on
page 81.
8. Open the cover. See “Opening the computer cover” on page 84.
9. Check the power switch/LED assembly connector on the system board. See
“Locating parts on the system board” on page 83. 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 96.
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.
v Machine type and model
v Processor or hard disk upgrades
v Failure symptom
– Do diagnostics indicate a failure?
– What, when, where, single, or multiple systems?
– Is the failure repeatable?
– Has this configuration ever worked?
– If it has been working, what changes were made prior to it failing?
– Is this the original reported failure?
v Diagnostics version
– Type and version level
v
Hardware configuration
– Print (print screen) configuration currently in use
– BIOS level
42 Hardware Maintenance Manual
