Acer Aspire 4250, Service Manual, Page: 144 / 200

4-16 Troubleshooting
Intermittent Problems
0
Intermittent system hang problems can be caused by a variety of reasons that have
nothing to do with a hardware defect, such as: cosmic radiation, electrostatic discharge,
or software errors. FRU replacement should be considered only when a recurring
problem exists.
When analyzing an intermittent problem, perform the following:
1.
Run the advanced diagnostic test for the system board in loop mode at least 10 times.
2.
If no error is detected, do not replace any FRU.
3. If an error is detected, replace the FRU. Rerun the test to verify that there are no
more errors.
Undetermined Problems
0
The diagnostic problems do not identify which adapter or device failed, which installed
devices are incorrect, whether a short circuit is suspected, or whether the system is
inoperative.
Perform the following procedures to isolate the failing FRU (do not isolate non-defective FRU).
NOTE: NOTE :
Verify that all attached devices are supported by the computer.
NOTE: NOTE :
Verify that the power supply being used at the time of the failure is operating
correctly. (Refer to
Power On Issues ).
1. Remove power from the computer.
2. Visually check components 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 external devices
Battery pack
Hard disk drive
DIMM
CD-ROM/Diskette drive Module
PC Cards
4. Apply power to the computer.
5. Determine if the problem has changed.
6.
If the problem does not recur, connect the removed devices one at a time until failing
FRU is found.
7.
If the problem remains, replace the following FRUs:
System board
LCD assembly