LG LH-CX640 Series Service Manual page 32

3-15
(B)
Hi-Fi Playback
YES
YES
YES
YES
PB
mode
No
Sound.
Check
the
Vcc of
IC801
(Pins34,40)
Check
the
Hi-Fi
Selection switch.
(IC801
Pin41)
and
the Tape quality.
Is
the
RF
Envelope
at
IC801
Pin44
over
2Vp-p?
YES
Check
IC801
Pin42(Data),
Pin43(Clock)
YES
Do
Audio
Signals
appear
at
IC801
Pin16(L-CH),
17(R-CH)?
YES
Do
Audio
Signals
appear
at
IC802
Pin10(L-CH),
16(R-CH)?
YES
YES
YES
Do
Audio
Signals
appear at
IC802
Pins22,
26?
Do
Audio
Signals
appear
at
JK801?
Check
Power 5.2V,
12VT.
NO
Check
IC501
Pin25
(A.H/SW)
NO
NO
Check
the
parts
of
\316\274-COM
(IC501
Pins59, 60)
NO
Check
the
Connection
at
P3D01
Pins7,
9.
NO
Check
the
A.IN
line
of
IC802(C808,
C809)
NO
Check the Vcc
of
IC802
Pin4.
Replace
IC802.
Check
the
Jack(JK801)
NO
NO
Check
Power.
NO