Acer 7520, 7220 manual Undetermined Problems

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: Verify that the power supply being used at the time of the failure is operating correctly. (See “Power System Check” on page 77.):

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:

qNon-Acer devices

qPrinter, mouse, and other external devices q Battery pack

q Hard disk drive

qDIMM

qCD-ROM/Diskette drive Module

qPC Cards

4.Power-on the computer.

5.Determine if the problem has changed.

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:

qSystem board

qLCD assembly

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