Service manual

SyncMaster 150T 4-1

4 Troubleshooting

Notes: 1. Before troubleshooting, setup the PC’s display as below.

• Resolution: 1024 x 768

• H-frequency: 48 kHz

• V-frequency: 60 Hz

2. If no picture appears, make sure the power cord is correctly connected.

3. Check the following circuits.

• No raster appears: Audio PCB, SMPS PCB, Main PCB

• 12V develop but no screen: Main PCB

• 12V does not develop: Audio PCB, SMPS PCB

4. If you push and hold the “EXIT” button for more than 5 seconds, the monitor automatically turns back

to the factory preset.

4-1 No Power

Does proper DC 12V appear at

DC jack connected to CN102?

Check DC Adaptor.

Yes

Does proper DC 5V appear at

output Pin of IC100?

Check IC104.

Check Q101, Q102 and Q103.

Yes

Does proper 5V-signal

appear at Pin 42 of IC701

(SW-REG-EN)?

Check IC701 and related circuit.

(CN100, Function Key)

Yes