Gateway P-79, Service Manual

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155
Keyboard and touchpad
Intermittent problems
Intermittent system hang problems can be caused by a variety of reasons that have nothing
to do with a hardware defect. These reasons include: cosmic radiation, electrostatic
discharge, or software errors. FRU replacement should be considered only when a recurring
problem exists.
To analyze an intermittent problem:
1
Run the advanced diagnostic test for the system board in loop mode at least ten times.
•
If any error is detected, replace the FRU.
•
If no error is detected, do not replace any FRU.
2
Rerun the test to verify that there are no more errors.
Undetermined problems
If the diagnostic test may not identify which adapter or device failed, which installed
devices are incorrect, whether a short circuit is suspected, or whether the system is
inoperative. Use these procedures to isolate the failing FRU (do not isolate a non-defective
FRU).
To isolate a failing FRU:
1
Turn off the notebook.
2
Visually check FRU parts for damage. If you identify any damage, replace the FRU.
3
Remove or disconnect all of the following devices:
Symptom / Error Action in Sequence
The keyboard (one or more keys) does not
work.
■
Reconnect the keyboard cable.
■
Test or replace the keyboard.
■
Test or replace the system board.
The touchpad does not work.
■
Reconnect the touchpad cable.
■
Test or replace the touchpad board.
■
Test or replace the system board.
Important
If you cannot find a symptom or an error in this list and the problem remains, see
“Undetermined problems” on page 155 .
Important
Verify that all attached devices are supported by the notebook.
Important
Verify that the power supply being used at the time of the failure is operating
correctly. ( See “Testing the power system” on page 141. )