Acer Aspire 1400, Service Manual

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Chapter 4 71
Keyboard or Auxiliary Input Device Check
Remove the external keyboard if the internal keyboard is to be tested.
If the internal keyboard does not work or an unexpected character appears, make sure that the flexible cable
extending from the keyboard is correctly seated in the connector on the main board.
If the keyboard cable connection is correct, run the Keyboard Test. See “System Diagnostic Diskette” on page
48 for more details.
If the tests detect a keyboard problem, do the following one at a time to correct the problem. Do not replace a
non-defective FRU:
1. Reconnect the keyboard cables.
2. Replace the keyboard.
3. Replace the main board.
The following auxiliary input devices are supported by this computer:
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Embedded numeric keypad
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External keyboard
If any of these devices do not work, reconnect the cable connector and repeat the failing operation.
Memory Check
Memory errors might stop system operations, show error messages on the screen, or hang the system.
1. Boot from the diagnostics diskette and start the doagmpstotics program (please refer to “System
Diagnostic Diskette” on page 48.
2. Go to the diagnostic memory in the test items.
3. Press F2 in the test items.
4. Follow the instructions in the message window.
NOTE: Make sure that the DIMM is fully installed into the connector. A loose connection can cause an error.
Power System Check
To verify the symptom of the problem, power on the computer using each of the following power sources:
1. Remove the battery pack.
2. Connect the power adapter and check that power is supplied.
3. Disconnect the power adapter and install the charged battery pack; then check that power is supplied by
the battery pack.
If you suspect a power problem, see the appropriate power supply check in the following list:
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“Check the Battery Pack” on page 72