LG 42LGX (CHASSIS:LA84B) Service Manual ▷ View online
C
2008
- 21 -
Ch
eck JK
700,
JK70
2.
Can y
ou see t
h
e n
o
rmal
w
a
v
e
form?
JK700,JK702
may
ha
v
e
pro
b
lem. Replace this Jack.
Check th
e in
put (Pin
A
L
21,
A
M
2
1
,A
N
2
1 a
nd Pin
A
N
2
2
,A
L22,
A
P
22)
of BCM3553(I
C100).
Measure
w
a
v
e
form at C638,
C639,C
640 an
d C628,C629,C630
becau
se it
ís more easy
to
check.
Can y
o
u see t
h
e n
o
rmal
w
a
v
e
form?
YES
NO
NO
This board ha
s big
problem
because Main chip(BCM3553) ha
v
e
some troubles.
A
ft
e
r ch
ec
kin
g th
orou
ghly
all p
a
th
once ag
ain
, You
sho
uld d
ecid
e
to rep
lace BCM
3553 o
r n
o
t.
Check all p
o
w
e
r d
o
main
o
f
FRC-945
9M (IC100
0)
(3.3V, 1.3V_C
ORE,1.3V_PL
L,3.3V,1.8V,2.5V)
& cr
y
s
tal output (X1000 / 20.25MHz)&FR
C_RESET
Measure Po
w
e
r &
w
a
v
e
for
m
at L1008,L1007,L1002,L1013,
L
1014,L
101
5~
L
1018&
C10
06
&R10
29
becau
se it
ís more easy
to
check.
Can y
ou see t
h
e n
o
rmal
w
a
v
e
form?
YES
This board ha
s big
problem
because FRC chip(FRC-9459M) hav
e
some troubles.
A
ft
e
r checking thoroughly
all path
once
again, You should decide
to replace
FRC-945
9M.
A
lthough y
ou
replace it, y
ou cannot see normal display
, decide to replace
M
a
in
c
h
ip
(B
C
M
3553
)
YES
Component
C
2008
- 22 -
Ch
eck JK
705.
Can y
ou see t
h
e n
o
rmal
w
a
v
e
form?
YES
JK70
5 ma
y
h
a
v
e
p
roblem. R
e
place th
is Jack.
NO
Check the input (Pin
A
K
16,A
N
1
5,
A
M
15,
A
H16,
A
J
16)
of BCM355x(I
C100).
Measure
w
a
v
e
form at C635,
C636,C
637 an
d R755,R758
becau
se it
ís more easy
to
check.
Can y
o
u see t
h
e n
o
rmal
w
a
v
e
form?
NO
This board ha
s big
problem
because Main chip(BCM3553) ha
v
e
some troubles.
A
ft
e
r ch
ec
kin
g th
orou
ghly
all p
a
th
once ag
ain
, You
sho
uld d
ecid
e
to rep
lace BCM
3553 o
r n
o
t.
Check all p
o
w
e
r d
o
main
o
f
FRC-945
9M (IC100
0)
(3.3V, 1.3V_C
ORE,1.3V_PL
L,3.3V,1.8V,2.5V)
& cr
y
s
tal output (X1000 / 20.25MHz)&FR
C_RESET
Measure Po
w
e
r &
w
a
v
e
for
m
at L1008,L1007,L1002,L1013,
L
1014,L
101
5~
L
1018&
C10
06
&R10
29
becau
se it
ís more easy
to
check.
Can y
ou see t
h
e n
o
rmal
w
a
v
e
form?
YES
This board ha
s big
problem
because FRC chip(FRC-9459M) hav
e
some troubles.
A
ft
e
r checking thoroughly
all path
once
again, You should decide
to replace
FRC-945
9M.
A
lthough y
ou
replace it, y
ou cannot see normal display
, decide to replace
M
a
in
c
h
ip
(B
C
M
3553
)
YES
RGB PC
- 23 -
C
2008
Check input connect JK600,
JK601,JK708
Can y
ou see t
h
e n
o
rmal
w
a
v
e
form?
Check DDC commu
nication lines
(IC601, IC602,
IC603, IC701)
JK60
0,JK6
01,
JK70
8 ma
y
h
a
v
e
p
roblem. R
e
place th
is Jack.
Check the output of
PI3HDMI341
A
T
R(IC600)
_HDMI1,2,3
or
TMDS1
4
1
H
A
R(
IC
7
0
3)
_HDMI4
.
.
Can y
ou see t
h
e n
o
rmal
w
a
v
e
form?
A
ft
e
r checking the Po
w
e
r
of this chip, y
o
u should
decide to
replace this or not.
Check HD
CP co
mmunicatio
n lin
es(IC102)
A
ft
e
r checking the Po
w
e
r
of this chip, y
ou should
decide to replace this or not.
YES
YES
YES
NO
NO
NO
NO
This board ha
s big
problem
because Main chip(BCM3553) ha
v
e
some troubles.
A
ft
e
r ch
ec
kin
g th
orou
ghly
all p
a
th
once ag
ain
, You
sho
uld d
ecid
e
to rep
lace BCM
3553 o
r n
o
t.
Check all p
o
w
e
r d
o
main
o
f
FRC-945
9M (IC100
0)
(3.3V, 1.3V_C
ORE,1.3V_PL
L,3.3V,1.8V,2.5V)
& cr
y
s
tal output (X1000 / 20.25MHz)&FR
C_RESET
Measure Po
w
e
r &
w
a
v
e
for
m
at L1008,L1007,L1002,L1013,
L
1014,L
101
5~
L
1018&
C10
06
&R10
29
becau
se it
ís more easy
to
check.
Can y
ou see t
h
e n
o
rmal
w
a
v
e
form?
YES
This board ha
s big
problem
because FRC chip(FRC-9459M) hav
e
some troubles.
A
ft
e
r checking thoroughly
all path
once
again, You should decide
to replace
FRC-945
9M.
A
lthough y
ou
replace it, y
ou cannot see normal display
, decide to replace
M
a
in
c
h
ip
(B
C
M
3553
)
YES
HDMI
- 24 -
C
2008
A
T
/NT Tune
r
BCM3553
SIF
IF_V
SB/
QAM
SD_
S
IF1
ED
S
A
FE_I
F_
N
ED
S
A
FE_IF_P
PI
3HDMI
3
4
1
ART
HDMI0
HDMI_RX
_
0
_
CL
K_N
HDMI_RX
_
0
_
CL
K_P
H
D
M
I_
R
X_0_
D
A
T
A
0_N
H
D
M
I_
R
X_0_
D
A
T
A
0_P
H
D
M
I_
R
X_0_
D
A
T
A
1_N
H
D
M
I_
R
X_0_
D
A
T
A
1_P
H
D
M
I_
R
X_0_
D
A
T
A
2_N
H
D
M
I_
R
X_0_
D
A
T
A
2_P
C
S
5345
(Audio SW
&A/D&)
AV
1
COMP
1
COMP
2
RGB
I2
S_
C
L
K_I
N
I2
S_
D
A
T
A
_I
N
I2
S_
L
R
_I
N
I2
S_
C
L
K_O
U
T
I2
S_
D
A
T
A
_OU
T
I2
S_
L
R
_O
U
T
N
T
P3000
(D-AMP)
A
UD_
SPD
IF
buffer
SPDIF out
C
o
axia
l o
u
t
A
U
D
_
LE
FT
_P
A
UD_
R
IG
H
T_P
MNT out
TMD
S
141H
AR
HDMI_RX
_
1
_
CL
K_N
HDMI_RX
_
1
_
CL
K_P
H
D
M
I_
R
X_1_
D
A
T
A
0_N
H
D
M
I_
R
X_1_
D
A
T
A
0_P
H
D
M
I_
R
X_1_
D
A
T
A
1_N
H
D
M
I_
R
X_1_
D
A
T
A
1_P
H
D
M
I_
R
X_1_
D
A
T
A
2_N
H
D
M
I_
R
X_1_
D
A
T
A
2_P
HDMI1
HDMI4
TPA3005D2
PHPR
G
4
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