Samsung LA22B350F2, Service Manual

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4-7
4. Troubleshooting
4-1-4. No Video (Tuner_CVBS)
Symptom Audio is normal but no picture is displayed on the screen.
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Major
checkpoints
Check the Tuner CVBS source
Check the M-star
This may happen when the LVDS cable connecting the Main Board and the Panel is disconnected.
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-
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Diagnostics
LA22B350F2 LA22B450C8
No
Check a B+ voltage (#2 of Tuner) 5V,
change a main PCB ass’y.
No
No
Power Indicator is off.
Lamp on, no picure.
Yes
Change a main PCB ass’y.
Does the signal appeat #8 of TU2400?
Does the Signal appear at C4022
of IC4000?
Check the LVDS cable?
Replace the LCD panel?
Please, Call to Samsung Co. LTD.
Yes
Connect the RF cable and
check RF signal.
Yes
Yes
Caution Make sure to disconnect the power before working on the IP board.