Samsung SyncMaster 320TSn-2, Service Manual

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4-2
4. Troubleshooting
4-2. No Power
Symptom
When turning on the Power button after connecting the power, the LED at the front of the
monitor does not operate.
-
Major
checkpoints
Check the IP board power fuse and the IP board output power.
Check the connections for the IP board and the Main board inside the monitor.
Check the LED of Power & IR function board and connections between the function assy and
main board.
Check the Main board power part and check also whether there is any abnormal output at other
output terminals.
-
-
-
-
Diagnostics
CN601
BD605
C602
C636
C640
C628
Yes
No
Does 5.3 V appear at Pin #4 of CN601
Does DC 12V appear at BD605?
No
Yes
No
Does DC 12V appear at C602?
①
Yes
No
Does 1.26V appear at C628?
③
Yes
No
Check the SMPS Board.
Check the LCD Panel.
Check the peripheral circuit of
CN601.
Replace IC604.
Replace IC603.
Replace IC602.
Does DC 2.5V appear at C640?
Yes
The Scaler is abnormal.
Replace the main board.
No
Does 3.3V appear at C636?
②
Yes
Caution Make sure to disconnect the power before working on the IP board.