165 Chapter 4

Undetermined Problems

The diagnostic problems does not identify which adapter or device failed, which installed devices are incorrect,
whether a short circuit is suspected, or whether the system is inoperative.
Follow these procedures to isolate the failing FRU (do not isolate non-defective FRU).
NOTE: Verify that all attached devices are supported by the computer.
NOTE: V erify that the power supply being used at the time of the failure is operating correctly. (See “Power On
Issue” on page 149):
1. Power-off the computer.
2. Visually check them for damage. If any problems are found, replace the FRU.
3. Remove or disconnect all of the following devices:
Non-Acer devices
Printer, mouse, and other extern al devices
•Battery pack
Hard disk drive
•DIMM
CD-ROM/Diskette drive Module
PC Cards
4. Power-on the computer.
5. Determine if the problem has chang ed.
6. If the problem does not recur, reconnect the removed devices one at a time until you find the failing FRU.
7. If the problem remains, replace the following FRU one at a time. Do not replace a non-defective FRU:
System board
LCD assembly