No Pc(D-Sub) Video - Samsung 320TSn-2 Service Manual

4. Troubleshooting

4-3. No PC(D-SUB) Video

Symptom Though the LED power turns on, the screen is blank when connecting the VGA cable.
-
Check the D-sub cable connections.
-
Check whether the LVDS cable is connected correctly to the panel.
Major -
checkpoints
Check whether the lamp connector of the panel is connected correctly to the IP board.
-
Check the circuit related PC input and scaler operation.
-
Diagnostics
Does the LED light up when turn on
Does 5V appear at Pin 10 of CN101
Does the waveform as the figure at Pin
17 ( H-sync) ⑤ and Pin 8 (V-sync) ⑥
Is TX** signal sent to Pin 16 and 17 of
Check the cable between the main
board and panel and replace the LCD
Caution Make sure to disconnect the power before working on the IP board.
4-4
C603
the power?
YES
D-Sub?
YES
of IC302 appear?
YES
CN401?
YES
panel.
CN401
IC302
CN101
No
Check the power port.
No
Check the cable connection.
No
Replace IC102.
No
The Scaler(IC302) is
abnormal. Replace the main
board