LG 42LG3000 (CHASSIS:LD84A) Service Manual ▷ View online
- 25 -
RGB PC doesn t displa
y
Check J703 ,
Can you see the normal
waveform?
Check the input of RGB Audio
switch(IC1001) ,
Can you see the normal waveform?
Check the output of RGB Audio
switch(IC1001) ,
Can you see the normal waveform?
YES
YES
YES
NO
J703
may have problem. Replace this Jack.
NO
After checking the Power of RGB Audio
switch, you should decide to replace
RGB Audio switch or not.
NO
After checking the Power of RGB Audio
switch you should decide to replace
RGB Audio switch or not.
Check the output of Main IC(IC100).
Especially you should check
The H,V sync and clock.
Can you see the normal waveform?
YES
NO
After checking the Power of Main
IC(IC100) you should decide to replace
Main IC or not.
This board has big problem because
Main IC(IC100) have some troubles.
After checking thoroughly all path once
again, You should decide to replace
Main Board or not.
Check the input of RGB Video
switch(IC700) ,
Can you see the normal waveform?
NO
After checking the Power of RGB Video
switch, you should decide to replace
RGB Video switch or not.
YES
- 26 -
HDMI doesn t display
Check input connect J900 , J901,
J902
Can you see the normal
waveform?
Check DDC communication
lines(IC900, IC901, IC903 Pin5,6)
Check the input of HDMI
Seitch(IC902)
This signal is TMDS.
Can you see the normal waveform?
YES
YES
NO
J900 , J901, J902
may have problem. Replace this Jack.
Check the output of HDMI
Switch(IC902).
Can you see the normal waveform?
YES
YES
NO
After checking the trace of TMDS lines and
power of HDMI Switch, you should decide to
replace HDMI Switch or not.
NO
NO
After checking the Power of this chip,
you should decide to replace this or not.
After checking the Power of HDMI
Switch you should decide to replace
MST3361 or not.
YES
Check HDCP communication
lines(IC902)
NO
After checking the Power of this chip,
you should decide to replace this or not.
Check the output of Main IC(IC100).
Especially you should check
The H,V sync and clock.
Can you see the normal waveform?
YES
NO
After checking the Power of Main
IC(IC100) you should decide to replace
Main IC or not.
This board has big problem because
Main IC(IC100) have some troubles.
After checking thoroughly all path once
again, You should decide to replace
Main Board or not.
- 27 -
BLOCK DIAGRAM
LVDS
S
C
2_L/
R_
IN
Saturn3+
S
T
M
A
V340
(I
C
700
)
NT
P3000A
(IC1000)
SP
(R)
SP
(L)
P1000
5
V
_ANT
_MNT
CI Slot
(P800)
EEP
RO
M
K
IA7427 (IC
104
)
24
C512
(I
C
105
)
I2
C_
D_
T
U
/
I2
C_
A
_
T
U
KE
Y
1
/2
TV Tuner
B
OOSTER
SIF
TV
_CV
BS
DDR Memor
y
256Mb (IC3
00)
SC1_R/G
/B
DSUB
_R/
G/B
R/
G/
B
P
C
_L/
R_
IN
COMP
_
Y
/P
b/
Pr
COMP
_
L
/R_
IN
DSUB
_H/
V
_S
Y
N
C
M
A
X3232
(I
C
702
)
DDC/U
A
RT-T
x
/Rx
HDMI
Sw
itch
(IC902)
EEP
RO
M
HDMI_
I2
C
HDMI_
I2C_
0
HDMI_CEC/Rx/
HPD
TM
D
S
x
3
HP
D x
3
HD
M
I_C
E
C
x
3
USB
_DM/DP
5
V
_HDMI
PCM_ADD
PCM_DATA
TS_Parallel
TU_T
S
_DA
TA
KIC7SZ32FU
(I
C
802
)
PCM_CD_ON
C
I_
C
D_1/2
II
S
MUTE
L
E
D_
G/R &
IR
Flash Memor
y
4MB (IC101)
S
C
1_
CV
BS_I
N
S
C
2_
CV
BS_I
N
S
C
1_T
V_VO
U
T
DTV/MNT_V
_
OUT
S
C
1_L/
R_
IN
T
V
_L
/R
_O
U
T
DTV/MNT_
L/R
_
OUT
LCD Panel
52/47/42/37
: F
H
D
32: : HD
RES
ET
I2
C
I/O Expander
(IC103)
I2
C
_
A_
T
U
TS_Serial
74LV
C
541A
(I
C
800
)
Flash Memor
y
4MB (IC102)
DDR Memor
y
256Mb (IC3
00)
EEP
RO
M
EEP
RO
M
Side_Y/C/V/L/R
SPDIF Out
IIC(E
ye
Q II)
T
P
A6110A2
(I
C
1002
)
Head phone Out
74
H
C
4066
(I
C
1001
)
- 28 -
EXPLODED VIEW
801
803
805
806
804
802
550
830
540
821
400
522
530
300
120
122
510
500
901
900
121
200
200T
200N
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.
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
Click on the first or last page to see other 42LG3000 (CHASSIS:LD84A) service manuals if exist.