DOWNLOAD LG 50LS4000 (CHASSIS:LA21B) Service Manual ↓ Size: 5.61 MB | Pages: 43 in PDF or view online for FREE

Model
50LS4000 (CHASSIS:LA21B)
Pages
43
Size
5.61 MB
Type
PDF
Document
Service Manual
Brand
Device
TV / LCD
File
50ls4000-chassis-la21b.pdf
Date

LG 50LS4000 (CHASSIS:LA21B) Service Manual ▷ View online

- 21 -
9. Digital TV Audio
Check RF Cable & Signal
Follow procedure 
‘8. 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. Analog TV Audio
Check RF Cable & Signal
Follow procedure 
‘8. 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 Tuner. Replace Tuner.
- 22 -
11. AV Audio
12. Component Audio
13. RGB Audio
Check AV Cable for damage
for damage or open conductor
Check JK1601 Signal Line
R1632,R1633
ok
ok
No
Replace Jack
Follow procedure 
‘8. All source audio’
trouble shooting guide.
Check Component Cable
for damage or open conductor.
Check JK1601 Signal Line
R1618, R1617
ok
ok
No
Replace Jack
Follow procedure 
‘8. 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 
‘8. All source audio’
trouble shooting guide.
- 23 -
BLOCK DIAGRAM
R
G
B
 P
C
S
P
D
IF
Co
m
po
ne
nt
 2 1
H
/P
 O
U
T
H
D
MI
(D
V
I)
H
al
H
al
N
IM
N
IM
(S
I2
1
(S
I2
1
7
6
_
A
T
7
6
_
A
T
SC
_
1
I
SC
_
1
I
N
P
U
T)
N
P
U
T)
P
C A
ud
io
 I
n
IF
 +
/-
TU
_C
VB
S
SI
F
L/
R
S
7
LR
S
ER
IA
L F
LA
S
H
M
X
IC
 (
8
M
 b
it
)
M
X
2
5
L8
00
6
EM
2
I
LV
D
S
(F
H
D
/H
D
 6
0
z)
A
. A
MP
N
TP
7
5
0
0
U
S
B
2
.0
D
P/
D
M
S
P
K
 L
/R
X
-t
al
2
4
M
H
z
FP
C
(5
1
P
/F
H
D
)
I2
S
SP
D
IF
H
/P
 L
/R
L/
R
CV
BS
Y/
Pb
/P
r,
 L
/R
RG
B/
H
/V
R
ea
r
TM
D
S
D
D
R2
 A
dd
.
D
D
R2
 D
at
a
SP
I
A
V
Si
de
N
A
N
D
  F
la
sh
(1
G
b
it
)
N
A
N
D
0
1
G
W
3
B
2
C
N
6
E
PC
M
_A
[0
:7
]
TM
D
S
H
D
MI
CV
BS
L/
R
D
D
R
2
5
6M
B
 1
G
b
H
yn
ic
H
5
TQ
1
G
6
3D
FR
D
D
R
2
5
6M
B
(1
G
b)
 
H
yn
ic
H
5
TQ
1
G
6
3D
FR
C
O
N
TR
O
L
IR
 &
 L
ED
 /
(S
O
FT
 T
O
U
C
H
)
K
E
Y
1
K
E
Y
2
IR
L
E
D
_B
/L
G
 L
O
G
O
A
T2
4
C
1
0
24
B
N
-S
H
-T
1
M
bi
t
I2
C
R
S
-2
3
2
C
FP
C
(3
0
P
/H
D
)
MA
X
3
2
3
2
RS
23
2C
S
E
N
S
O
R
_S
C
L
S
E
N
S
O
R
_S
D
A
LA
N
ET
_RX
/T
X
- 24 -
200
800
820
120
530
540
810
910
900
521
400
A2
A1
0
A9
A7
* Set + Stan
d
* Stand Base   + Body
LV
1
EXPLODED VIEW
Many electrical and mechanical parts in this chassis have special safety-related characteristics. These 
parts are identified by       in the Schematic Diagram and EXPLODED VIEW. 
It  is  essential  that  these  special  safety  parts  should  be  replaced  with  the  same  components  as 
recommended in this manual to prevent X-RADIATION, Shock, Fire, or other Hazards. 
Do not modify the original design without permission of manufacturer.
IMPORTANT SAFETY NOTICE
300
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