Compal NBLB2, Service Manual

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To determine if the com
puter‟s keyboard is functioning properly, perform the following
procedures. Figure 6-5 outlines the process. Start with Procedure 1 and continue with
the other procedures as instructed.

Procedure 1: External keyboard check

Procedure 2: Diagnostic check

Procedure 3: Connector and replacement check
5.1 Procedure 1 External keyboard check
Connect a USB keyboard to one of the computer‟s keyboard/mouse ports, then boot
the computer. The computer automatically detects the external keyboard.
If the external keyboard works correctly, the internal keyboard or its connections may
be faulty. Go to Procedure 2.
If the external keyboard appears to have the same problem as the internal keyboard,
the system board may be damaged.
5.2 Procedure 2 Diagnostic test
Run the Diagnostic Program, which will automatically execute the Keyboard Test.
Refer to Chapter 3, Tests and Diagnostics for more information on how to run the
program.
If an error is located, go to Procedure 3. If an error does not occur, the keyboard is
functioning properly.
5.3 Procedure 3 Connector and replacement check
The keyboard and/or system board may be disconnected or damaged.
Replacement Procedures and perform the following checks.
Check 1
Make sure the keyboard cable is firmly connected to the system board.

If the connection is loose, reconnect firmly and repeat Procedure 2.

If there is still an error, go to Check 2.
Check 2
The keyboard may be damaged.

If the problem still exists, perform Check 3.
Check 3
The system board may be damaged. Replace it with a new one.