No Sound (Picture Ok) - LG PT-43 Service Manual

2. NO SOUND (PICTURE OK)

<AV1,2,3,SCART INPUT>
Waveform of AV Board IC7 01
#47,48,50,51,53,54,56,57
at each Mode ?
YES
Waveform of AV Board
IC701 #27,#28,#25 ?
Waveform of MAIN1
IC601 #7,#11 IC602 #7 ?
Waveform of MAIN1
IC601 #2,#4 IC602 #4 ?
Check AV Board JA501,
Main1 P602 Connector
NO
NO
YES
NO
YES
NO
YES
Check JA202 Jack
YES
Check around IC701
Check around AV Board
Q703,704,705
Check around
IC601,602
- 18 -
< RF >
Waveform of
NO
MAIN1 Q022(E)
( SIF ) ?
YES
Waveform of
NO
AV Board IC701
#67 ?
Check
TU101
Check
around
Q706