No Power - Samsung 820DXn Service Manual

4. Troubleshooting

4-2. No Power

When turning on the Power button after connecting the power, the LED at the front of the
-
Symptom
monitor does not operate.
Check the IP board power fuse and the IP board output power.
-
Major Check the connections for the IP board and the Main board inside the monitor.
-
checkpoints
Check the Main board power part and check also whether there is any abnormal output at other
-
output terminals.
Diagnostics
Does DC 12V appear at BD643?
Does DC 1.8V appear at C603?
Does 3.3 V appear at Pin 16 ofCN602?
Caution Make sure to disconnect the power before working on the IP board.
4-2
CN602
C653
Does 5.2 V appear at Pin #15 of
CN602
Yes
Yes
Does DC 12V appear at C653?
Yes
Does 3.3V appear at C622?
Yes
Yes
BD643
C622
C603
Main Board Front
No
No
No
No
No
③
No
Check the SMPS Board.
Check the LCD Panel.
Check the peripheral circuit of
CN602.
Replace IC602.
Replace IC601.
The Scaler(IC408) is
abnormal.
Replace the main board.