No Audio Output - Eiki LC-XT4U Service Manual

Troubleshooting
●
No Power
Check the Unit_ Sub Power.
K66L
25V
FAN-ON/OFF
TP7614
K66A
UNIT_SUB-POWER
●

No Audio Output

Audio signal processing circuit
Terminal board
- DVI
ASS'Y CGMOTHER
SLOT_1
K90C
L 33
K80H
R 122
Terminal board
- Component
SLOT_2
K90D
L 33
K10H
R 122
13
Terminal board
- AV
SLOT_3
K90E
L 33
K3101
R 122
Terminal board
- DSUB-15
SLOT_4
K90F
L 33
K71H
R 122
FAN_A24V
FL FL
FAN_A24V
3 1 2 2 3
K66G K66E
Q1 Q23 Q5
FAN-A ADJ.
FAN-ON/OFF
Q2
TP7611
6.35V 6.35V
16V
9V
-6V 16V
-6V
PWR-SW
ASS'Y_MAIN
IC5004
L L
5 7
38 L
R R
3 1
3 37 R
K90Q K8A K8J
IC1801
I/O
EXPANDER 36
FAN_B12V FAN_B12V
FL
FAN_C12V
3 1 2 6
K66F
FAN-ON/OFF
Q9
FAN-A ADJ.
FAN-A ADJ.
CONTROL
FAN-B ADJ.
PF
FAN-B ADJ.
Q6
FAN-C ADJ. CONTROL
IC6
I/O EXP
FAN-C ADJ.
Q18
Q16
Q12
Q14
- Check Point -
Terminal board DVI, Component, AV, and
DSUB-15.
1. Check that the R and L signals are correct.
Pins122(R) and 33(L).
K80H, K10H, K3101, K71H.
Assembly CG-Mother
1. Check that the R and L signals are correct.
Pins 3(R) and 13(L) of IC9002.
ASS'Y_RS232C
Assembly Main
L
1
1. Check that the Vcc-voltages are correct.
K38H
2. Check that the L and R input signals are cor-
R
3
rect.
Pins 5(L) and 3(R) of IC5004
3. Check that the IC5004 output signals are cor-
rect.
Pins 7(L) and 1(R) of IC5004.
Assembly RS232C
1. Check that the L and R output signals are cor-
rect.
- 62 -
IC5
IC1
I/O EXP
IC2
SCL/SDA
PWR-SW
S9.6V
S3.3V
S6.35V
5VB
16VA
-5V
16VB
K66D
FAN_C12V
SCL/SDA
PWR-SW