LG DR-7400 Service Manual page 19

When Front RCA Input, No Audio Output
DISC PLAY Audio Out
is normal?
YES
IC708 - 1,14 pin
No Audio Signal input ?
YES
IC709 -23, 27 pin
Audio Signal is okey?
YES
IC714-10, 12 pin
Audio signal okey?
YES
When L3 Input
PIM02,PMI02 18, 19, 20, 21pin
are okay?
YES
Check RCA JACK and other circuits
NO
Check 'When Playin g Disc , No Audi o Output'
NO
Audio signal path from front AV to IC708 and
check CSI03(2, 3pin)
NO
Check IC709 and other circuit
NO
Check signal path from IC709, IC714, Check IC706
NO
Check Connector PIM02 & PMI02
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