Sanyo PLC-EF12B, Service Manual

Page: 46 / 112

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Troubleshooting
7
SWITCH
IC5101
SWITCH
IC5001
Q5061
BUFFER
Q5042
Q001
BUFFER
Q003
AUDIO
AMP
IC001
AV1 AUDIO INPUT
AV2 AUDIO INPUT
CG1 AUDIO INPUT
CG2 AUDIO INPUT
AUDIO
CONTROL
IC5121
Q5142
BUFFER
Q5143
INTERFACE BOARD
MOTHER BOARD
AV JACK BOARD
R:5
L:2
9 10
4
15
R:3
L:1
R
L
R
L
POWER FAIL
16V
10
7
2
5
L
R
AUDIO MUTE
SPEAKER OFF
SPEAKER
SPEAKER
3
R:11 L:4
9 10
14
1
L
R
R:15 L:2
13
19
3
2
9
10
SDA
SCL
14 7
L
R
1. Check that the Vcc-voltage( +9V) is correct.
2. Check that the AV/CG1/CG2 SELECT signal is cor-
rect.
Pin9, 10 of IC5101 ................................ Pin9 : Pin10
AV L : L
AV H : L
CG2 L : H
CG1 H : H
3. Check the input and output signals at IC5101.
4. Check the input and output signals at IC5121.
5. Check the signal at Pin9 of IC5121. (SDA)
Check the signal at Pin10 of IC5121. (SCL)
6. Check the input and output signals at Q5142.Q5143.
INTERFACE BOARD
1. Check that the Vcc-voltage(Pin16 of 9V) is
correct.
2. Check that the AV1/AV2 SELECT signal is correct.
Pin9, 10 of IC5001....................................... AV1 : H
AV2 : L
3. Check the input and output signals at IC5001.
Check the input and output signals at Q5061,
Q5042.
1. Check that the Vcc-voltage( +9V,+16V) is correct.
2. Check the input and output signals at Q001.Q003.
3. Check that the POWER FAIL signal is correct.
4. Check that the AUDIO MUTE signal is correct.
5. Check that the SPEAKER-OFF signal is correct.
6. Check the input and output signals at IC001.
MOTHER BOARD
AV JACK BOARD
NO SOUND