LG 37LH40 / 37LH41 (CHASSIS:LA92G) Service Manual ▷ View online
- 25 -
C
2009
9. Digital TV Audio
Check Tuner 5V Power
TU1001 4Pin
NO
Check IC1002, IC1003
OK
Check IF_P/N Signal
NO
Replace Tuner.
OK
Check Check Demodulator Input
Clock(X1005-25MHz)
NO
Replace X1005
OK
Check IC1004(LGDT3305) Output
- AR1070, AR1071
NO
Replace IC1004
OK
Check Output Signal
P600 1,2,3,4 PIN
NO
Replace NTP3100L
(Audio AMP) IC600
OK
Check Connector & P600
NO
Replace connector
if found to be damaged.
OK
Check speaker resistance
and connector damage.
NO
Replace speaker.
- 26 -
C
2009
11. No Video
Check 12V DC Voltage
L1300
NO
Check Q706
2V DC voltage (pin4)
NO
Check PANEL_CTRL
- LOW(0V)
OK
OK
Replace Q706
Check 3.3V/16V/26V DC Voltage
-R1447,R1446,R1450
NO
Replace IC1300
or Main borad
OK
Check IC1301 Vcom(pin 28)
- about 7V
NO
Detach the P1400/P1401
FFC Cable
NO
Replace IC1301
OK
OK
Replace LCD Module
Check URSA2 mini-LVDS output
P1400, P1401
NO
Replace LCD Module
Check FRC IC
NO
Replace Mstar(IC1100)
or Main board
1) FRC clock(X1100)
2) 3.3V, 1.8V, 1.26V
2) 3.3V, 1.8V, 1.26V
3) I2C signal (R1106,R1107)
OK
10. Analog TV Audio
Check Tuner 5V Power
TU1001 4Pin
NO
Check IC1002, IC1003
OK
Check SIF buffer signal.
NO
Check SIF Signal line.
OK
Follow procedure All source audio
trouble shooting guide.
NO
Replace Mstar(IC100)
or Main board
Check RF Cable
OK
C
2009
- 27 -
BLOCK DIAGRAM
D-sub RGB/JK120
3
HDMI 1/JK500
Side
A
V
/J
K
120
2
CV
BS
, L
/R
DDR2 (5
12Mb
it
)
Qimonda / Hy
nix
IC
1
NAND Flash
(512Mb
it)
IC102
Digita
l A
udio
(Optic
)/J
K601
Digita
l AMP
NT
P3100L
IC600
RS-232C (Ctrl./SVC)
JK1203
I2S
EE
PRO
M
512Kb
it
IC
104
RGB/
H/V
Tuner
TU1001
DD
R_Data[
0:
15]
, D
Q
S,
DM …
Ad
dr.[ ]
, ctrl. data
MAX3
232
IC1201
Saturn5
Saturn5
(ATSC
(ATSC
US)
US)
MPEG2
L
inux
Scal
er
IC100
D
a
ta [0 …
7
]
IF
+/-
SIF
TU_CVBS
R
e
set / IF
_AGC
…
SDA
/SCL_
5V
HDMI4/JK503
Ad
dr[0…1], C
S
…
Au
d
io L/R
A
u
dio L/R (for
RGB)/JK1205
HDMI 2/JK501
SP
DI
F
RX
/T
X
RX
/T
X
J
A
CK
P
A
CK
J
A
CK
P
A
CK
at RE
A
R
at RE
A
R
J
A
CK
P
A
CK
J
A
CK
P
A
CK
at SIDE
at SIDE
SCL
, SDA
_3
.3
V
T
R
B
u
ffer
VS
B Dem
o
d
.
IC
1004
LG
D
T
3305
X-t
al
X100
R
e
se
t Sw
it
ch / SW1
00
12MHz
T
S
In[0…
7]
TS_
cl
k, SOP, Va
l
EEPR
OM
Data[1
6:31]
DDR2 (5
12Mb
it
)
Qimonda / Hy
nix
IC
2
AV
Component 1
Y
Pb Pr, L/R
CV
BS
, Y/
C,
L
/R
Component 2
Y
Pb Pr, L/R
USB2.0/JK
120
4
SCL
, SDA
_3
.3
V
DP
/D
M
O.C. Protector
IC1202
+5V
+5V
LCD Module
(FHD,
120
H
z
)
FRC IC
(MST
7327)
IC1100
DDR2
IC
300/
IC
301
Qimonda/Hy
nix
FRC Block
FRC Block
T
T
-
-
c
on b
loc
k
c
on b
loc
k
LV
D
S
HDMI 3/JK502
HDMI S/W
T
D
A9996
IC502
Mini-LVDS
IIC
JK12
06
SP
K L/
R
V-Com
TPS65162
IC1300
P-Gamma
BUF
168
21
IC1300
IIC
Serial F
las
h Memor
y
for Boot / 32Mbit
IC104
SCL
, SDA
_3
.3
V
HDCP
EE
PRO
M
IC
105
SCL
, SDA
_3
.3
V
SP
I Fl
ash
2Mb
IC
1101
C
2009
- 28 -
3.
3
V
SDA_
0
SCL_0
SDA_
1
SCL_1
FE
_DEM
OD
_SD
A
FE
_DEM
OD
_SC
L
FE
_TUN
ER
_
S
DA
FE
_TUN
ER
_
S
CL
(SDA_
3
SC
L_3 )
EE
PROM_SDA
EE
PROM_SCL
(SDA_
2
SC
L_2 )
Mstar
0 o
h
m
2.7
K
o
h
m
MEMC_SD
A
MEMC_SCL
0 o
h
m
+3
.3
V
N
T
P
3100
L
T
D
A
9996
T
D
A
9996_S
D
A
T
D
A
9996_S
CL
0 o
h
m
0 o
h
m
2.7
K
o
h
m
S
D
A_
S
U
B
/AM
P
SCL_SUB/
A
M
P
0 o
h
m
100 o
h
m
T
D
V
-H
101F
22 o
h
m
22 o
h
m
4.7
K
o
h
m
+5
V
_
TU
+5
V
_
G
e
n
e
ra
l
4.7
K
o
h
m
A
T
24C512
33 o
h
m
22 o
h
m
4
.7
K oh
m
+
3
.3
V
+
5V_General
OPT
33 o
h
m
3.3
K
o
h
m
+3
.3
V
33 o
h
m
33 o
h
m
33 o
h
m
IR
0 o
h
m
M
S
T
7327
(URS
A
2
)
L
G
DT3305
22 o
h
m
IIC Map
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