LG GCC-4242N Service Manual page 60

No Audio Output
(CD-DA Play)
Audio Circuit Check.
Check output signal of
C401 and C402, IC201side.
OK
Check soldering of R401-R405
and C401-C404.
OK
Is IQ402(Base) High level?
OK
Is Q402 (Corector) Low level?
Check Soldering of Q401.
Replace Q401.
62
NG
NG
NG
NG
OK
NG
Check soldering of IC201.
Repair soldering or replace parts.
• Check soldering of IC201.
• Check soldering and value of R265.
Q402 is mute control transistor.
Q402 Corector hight level is audio
mute on, it low level is mute off .
Check soldering of Q402 .
Replace Q402.