Display Troubleshooting - Toshiba PORTEGE M400 Maintenance Manual

2.8 Display Troubleshooting

2.8 Display Troubleshooting
This section describes how to determine if the computer's display is functioning properly.
Start with Procedure 1 and continue with the other procedures as instructed.
Procedure 1: External Monitor Check
Procedure 2: Diagnostic Test Program Execution Check
Procedure 3: Connector and Cable Check
Procedure 4: Replacement Check
Procedure 1 External Monitor Check
Connect an external monitor to the computer's external monitor port, and then boot the
computer. The computer automatically detects the external monitor.
If the external monitor works correctly, the internal LCD may be damaged. Go to Procedure 3.
If the same problem as the internal monitor appears on the external monitor, the System board
may be damaged. Go to Procedure 2.
Procedure 2 Diagnostic Test Program Execution Check
The Display Test program is stored on the Diagnostics disk. Insert the Diagnostics disk in the
USB floppy disk drive, turn on the computer and run the test. Refer to Chapter 3, Tests and
Diagnostics for details.
This program checks the display controller on the System board. If an error is detected, go to
Procedure 3.
PORTEGE M400 Maintenance Manual (960-541) [CONFIDENTIAL]
2 Troubleshooting
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