Toshiba PTA71, PTA70, PSAA9 manual Troubleshooting Display, Procedure 1 External Monitor Check

2 Troubleshooting 2.7 Display

2.7 Display

To check if the computer’s display is defective or malfunctioning, follow the troubleshooting procedures below as instructed.

Procedure 1 External Monitor Check Procedure 2 Test Program Check

Procedure 3 Connector Check and 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 even if resume mode is enabled.

If the external monitor works correctly, the internal LCD, LCD/FL cable, or FL may be faulty. Go to Procedure 3.

If the external monitor appears to have the same problem as the internal monitor, the system board may be faulty. Go to Procedure 2.

Procedure 2 Test Program Check

Insert the diagnostics bootable CD in the computer's CD ROM, turn on the computer and run the test. See Chapter 3 for information on how to perform the test.

If an error is detected in the test, go to Procedure 3. If no error is detected, the display itself is normal.

Procedure 3 Connector Check and Replacement Check

The display unit has an LCD module, Fluorescent lamp (FL), panel close switch and FL inverter board. Any of the components or their connections may be defective. Disassemble the computer following the steps described in Chapter 4, then perform the following checks:

(1)If the FL does not light, perform Check 1.

(2)If characters or graphics are not displayed normally, perform Check 5.

(3)If the FL remains lit when the display is closed, the panel close switch may be defective. Perform Check 8.

Check 1 Make sure the following cables have been firmly connected to the system board and FL inverter board.

FL	FL inverter board	System board	CPU
	HV cable	LCD/FL cable

If any of the cables is loose or off, reconnect it firmly and return to Procedure 3. If there is still an error, perform Check 2.

Check 2 The LCD/FL cable may be faulty. Replace it with a new one and return to Procedure 3. If there is still an error, perform Check 3.

2-18 Satellite A100/A105 / TECRA A7 Maintenance Manual