Daewoo DV6T712D Service Manual page 20

A.d. AV-F E-E
No sound in AV-F E-E
mode
Is there Audio at IC253
pin#2,12 in AV-F mode?
YES
Is AV-F Audio signal output
at IC253 pin#14,15?
YES
Is there AV-F Audio at IC252
pin#5,14?
YES
Is AV-F Audio signal output at
IC252 pin#3,13?
YES
C at Q904 is L or H?
L
Check Output JACK.
NO
Is 12V obtained at IC253
pin#16?
IC601 pin#32 is L?
Is 3.5V obtained at IC253
pin#10,11?
Replace IC253
NO
NO
IC601 pin#27 H
Check
H
A.Mute is L
IC601.
or H?
L
Check Q904,Q905,
R937, R938, R939
Check Input JACK.
(FRONT AV)
NO
Check POWER circuit.
NO
Check IC601.
NO
Check R646, R647
Check signal flow circuit
IC251 , IC252.
Is 12V obtained at IC252
pin#16?
YES
IC601 pin#31 is L?
pin21 is H?
YES
Is about 3.5V obtained at
IC252 pin#9?
Is about 8V obtained at
IC252 pin#10?
YES
Replace IC252.
19
TROUBLESHOOTING
NO
Check POWER circuit.
NO
Check IC601.
NO
Check
R923,R924,R925,R926