2.9 Display Troubleshooting 2 Troubleshooting Procedures
2-42 PORTEGE M300 Maintenance Manual (960-504)
2.9 Display Troubleshooting To check if the computer’s display is malfunctioning or not, follow the troubleshooting
procedures below 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, then boot the computer.
The computer automatically detects the external monitor.
If the external monitor works correctly, the internal LCD may be faulty. Go to Procedure 3.
If the external monitor appears to have the same problem as the internal monitor, system
board may be faulty. Go to Procedure 2.
Procedure 2 Diagnostic Test Program Execution Check
The Display Test program is stored in Diagnostics disk. This program checks the display
controller on system board. Insert the Diagnostics disk in the USB FDD, turn on the
computer and run the test. Refer to Chapter 3, Tests and Diagnostics for details. If an error is
detected, go to Procedure 3.