LG PT-43, Service Manual

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Trouble Shooting
1. NO PICTURE ( SOUND OK )
Check MAIN1 Q026(E) Waveform.
CVBS Signal ?
(2Vpp)
Waveform of AV Board Q200(E) ?
Check Tuner(TU101) VIDEO output
NO
Check around
IC200
Waveform of AV Board IC202 #11 ?
Check around IC201, 202
NO
Waveform of MAIN1 IC501 #63 ? Check AV Board VQ202(E)
Waveform of MAIN1 P503 #5, #7, #9 ?
Check around IC501 #37, #38, #39
Output circuit.
Waveform of CPT Board
IC901R/G/B #3 ? Check around CPT Board
Q901R/G/B
Waveform of CPT Socket Cathode
(RK/GK/BK) ?
Check around IC901R,G,B
NO
NO
NO
NO
NO YES
YES
YES
YES
YES
YES