Samsung LEF22VS, Service Manual

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4-2
4. Troubleshooting
4-2. When the power does Not Turn on
Symptom
- When turning on the power button after connecting Adaptor, the LED at the front of the monitor
does not operate.
Major checkpoints
- Check the Adaptor power fuse and the Adaptor output power.
- Check the connections for Adaptor and the Main board inside the monitor.
- Check the Main board power part and also check whether there is any abnormal output at any of
the other output terminals
Diagnostics
IC602
IC601
CN700
Yes
Check the connection status for
the function ass’y.
Yes
Replace the Adaptor.
No
Is DC12V measured at pins2 of the
CN700 connector when pins 1,3 are
0V?
Is DC5V measured at C222 when pin2
of IC202 is DC 12V?
Check the circuits related to
IC202.
No
Yes
Check the circuits related to
IC605.
No
Is DC3.3V measured at pin3 of the
IC605 when pin1 is DC 5V?
Yes
Check and replace the Adaptor.
Check the circuits related to
IC601.
No
Is DC3.3V measured at pin3 of the
IC601 when pin1 is DC 5V?
Yes
Check the circuits related to
IC602.
No
Is DC1.8V measured at pin1 of the
IC602 when pin3 is DC 5V?
Yes
Caution Make sure to disconnect the power before working on the Adaptor.