LG 37LK456C (CHASSIS:LD0EC) Service Manual ▷ View online
- 21 -
Check the TV Speaker Menu.
(Menu → Sound → TV Speaker)
On
ok
ok
Check Output Signal P501
1, 2, 3, 4 pin.
Replace Audio AMP IC(IC501).
ok
No
Check Connector & P501.
Replace connector.
if found to be damaged.
ok
No
Check speaker resistance
and connector damage.
Replace speaker.
ok
No
Off
Toggle the Menu.
Check AMP IC(IC501) Power
24V or 20V or 15V, 3.3V
No
Replace Amp IC(IC501).
Check Mstar I2S Output
IC501 9,10,11 Pin.
No
Check signal line. Or replace Mstar(IC101).
Check Mstar AUDIO_MASTER_CLK
R148.
No
Replace Mstar(IC101) o r Main Board.
ok
Check AMP I2C Line
R140, R141.
No
Check signal line. Or replace Mstar(IC101).
9. All Source Audio
- 22 -
Check RF Cable & Signal.
Follow procedure
‘9. All source audio’
trouble shooting guide.
ok
Check Tuner 3.3V Power
L3703.
Replace L3703.
Check Tuner 1.8V Power.
IC3703 2 pin : 1.8V
Check IF_P/N Signal
TU3700 10/11 Pin.
Replace IC3703.
ok
ok
ok
No
No
No
Bad Tuner. Replace Tuner.
10. Digital TV Audio
Check RF Cable & Signal.
Follow procedure
‘9. All source audio’
trouble shooting guide.
ok
Check Tuner 3.3V Power
L3703.
Replace L3703.
Check Tuner 1.8V Power
IC3703 2 pin : 1.8V.
Check CVBS Signal
TU3700 8 Pin.
Replace IC3703.
ok
ok
ok
No
No
No
Bad Tubner. Replace Tuner.
11. Analog TV Audio
- 23 -
Check AV Cable for damage
for damage or open conductor.
Check JK1604 & Signal Line.
ok
ok
No
Replace Jack.
Follow procedure
'9. All source audio'
trouble shooting guide.
12. AV Audio
Check Component Cable
for damage or open conductor.
Check JK1602, JK1603
& Signal Line.
ok
ok
No
Replace Jack.
Follow procedure
'9. All source audio'
trouble shooting guide.
Check Cable conductors
for damage or open conductor.
Check JK1102 & Signal Line.
ok
No
ok
Replace Jack.
Follow procedure
'9. All source audio'
trouble shooting guide.
13. Component / SCART Audio
14. RGB Audio
- 24 -
R
G
B
P
C
SPDIF
C
om
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nt
1
H/P OUT
H
D
M
I1
/2
(D
V
I)
S
I2
17
6
S
I2
17
6
(L
G
IT
)
(L
G
IT
)
PC/DVI
A
udi
In
R
S-
23
2C
IF
+
/-
TU
_C
VB
S
SIF
L/
R
S
7L
R
IC
10
1
M
A
X3
23
2
M
A
X3
23
2
SE
R
IA
L F
LA
S
H
IC1401 (8
M
bit)
M
X
25
L8
00
5M
2I
SE
R
IA
L F
LA
S
H
IC1401 (8
M
bit)
M
X
25
L8
00
5M
2I
LVDS
(F
H
D
/5
0H
z)
A
ud
io
A
MP
N
TP
74
00
U
S
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2.
0
D
P
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M
S
P
K
L
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X
-ta
l
24
M
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C
(5
1P
)
I2
S
SP
D
IF
H
/P
L
/R
C
VB
S
, Y
/P
b/
P
r,
L/
R
R
G
B/
H
/V
R
S
23
2C
R
ea
r
TM
D
S
D
D
R
3
Ad
d.
D
D
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3
D
at
a
SP
I
AV
2
Side
N
A
N
D
F
LA
SH
IC102 (1Gbit
)
P
C
M
_A
[0
:7
]
TM
D
S
HDMI3
C
VB
S
, L
/R
D
D
R
3
1G
b
IC
12
02
H
5T
Q
1G
63
B
FR
D
D
R
3
1G
b
IC
12
01
H
5T
Q
1G
63
B
FR
C
O
N
TR
O
L
IR
&
L
E
D
/
SO
FT
T
O
U
C
H
(T
A
C
T
S
W
IT
C
H
)
SE
N
S
OR
_S
C
L/
SD
A
LE
D
_R
KE
Y1
KE
Y2
IR
LE
D
_B
SO
FT
T
O
U
C
H
_S
C
L/
SD
A
M
24
M
01
-H
R
M
N
6T
P
IC
10
4
25
6K
bi
t
I2
C
AV
2
C
V
BS
, L
/R
O
pt
io
n
F-SC
A
R
T
S
C
1_
C
V
B
S
_I
N
S
C
1_
R
/G
/B
FE
_V
O
U
T
CI Slot
74
LC
X
24
4
B
uf
fe
r
TS_
D
A
TA[0:7]
PC
M
_D
AT
A
[0
:7
]
FE
_T
S_
D
AT
A[
0:
7]
PC
M
_A
[8
:1
4]
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