Sanyo PLV-70, Service Manual

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Troubleshooting
IC1652
AUDIO
CONTROL
IC1632
R-AMP.
IC1631
L-AMP.
IC5011
AUDIO-SW
5
14
1
13
2
12
9
10
3
13
PC_L/R
PC_L/R
AV_L/R
Q5008
Q5007
VOLUME
SCL/SDA
A_MUTE
A_SW1
A_SW2
AU_SW2
L
AU_SW1
R
L
R
L
R
5
55
14
17
14
17
7
10
15
2
IC1801
I/O
EXPANDER
5
4
IC2381
D/A
8
3
2
49
IC801
MAIN
CPU
COMPUTER2
AUDIO IN
COMPUTER1
AUDIO IN
VIDEO
AUDIO IN
3
7 8
1
3
4
1
2
K10T
K16S
K16R
K8T
41
42
39
40
K10Q
K8B
K16U
AV BOARD
M DRIVE BOARD
MAIN BOARD
MUTE On: H
12
3,14
SPEAKERS
29, 30
No Sound
1. No audio signals at AV input circuit.
Check audio signals at pins 1, 13 (CG1), 5, 14 (CG2) and
2, 12 (VIDEO) of IC5011 on the AV Board. Check IC5011
and peripheral circuits.
2. Incorrect operation of Input mode switching.
Check AUDIO_SW1/AUDIO_SW2 switching signals at pins
9 and 10 of IC5011. The AUDIO_SW1/AUDIO_SW2 sig-
nals are output from pins 4 and 5 of IC1801. See the truth
table below for input mode selection.
3. No audio output signal at speakers.
Check audio signals at pins 3, 4 and 1, 2 of K16U on M
Drive Board.
Check MUTE signal at pin 8 of K16R/K8T.
The MUTE signal is output from pin 48 of IC1801.
Mute On : High
Check MUTE signal at pins 3 and 14 of IC1652.
Check sound volume signal at pin 7 of K16R/K8T.
The VOLUME signal is output from pin 8 of IC2381 and it
is controlled by IC801 via the IIC bus.
Volume Min.: Low
Check audio signals at IC1655,IC1631, IC1632 and periph-
eral circuits.
4. No power supply at audio circuit.
Check 9VA power supply line.
Logic Table of IC5011
Pin 10 Pin 9 Mode
L L COMPUTER 1
H L COMPUTER 2
L H VIDEO