Daewoo SD-8100, Service Manual

Page: 16 / 63

16
TROUBLESHOOTING
4. AUDIO (Hi-Fi MODEL)
No sound in RF E-E
mode
Is there Audio at IC252
pin#4,11?
IC601 pin#27
A.Mute is L or
H?
A. No sound in E-E mode
A. a.1 RF E-E
NO
Check IC101, RF101 block.
Is 12V obtained at IC252
pin#16?
Is RF Audio signal output at
IC252 pin#3,13?
Check POWER circuit.
NO
YES
NO
IC601 pin#31 is H, pin#21
is H?
Is about 8V obtained at
IC252 pin#9?
Is about 8V obtained at
IC252 pin #10?
YES
Check IC601.
Check
R298,R299,R646,R647.
NO
NO
C at Q904 is L or H?
YES
Check IC601.
Check Output JACK.
H
H
L
YES
Check Q904, Q905,
R937,R938,R939
L
Replace IC252.
YES