LG 52LB5DF-UL (CHASSIS:LA75A) Service Manual ▷ View online
- 21 -
Ch
eck JP7
032, JP7033, JP70
34.
Can
y
o
u
see t
h
e n
o
rmal
w
a
v
e
fo
rm?
Ch
eck th
e C6
35, C636, C6
37 in
fro
n
t o
f
BCM35
53.
Can
y
o
u
see t
h
e n
o
rmal
w
a
v
e
fo
rm?
YE
S
NO
JK70
5 ma
y
h
a
v
e
p
ro
b
lem. R
e
p
lace th
is Jack.
NO
A
fte
r c
h
ec
k
the
pa
tte
rn be
tw
een
input
of
BCM35
53 an
d
JK705 ,
Yo
u
can
su
spect th
at PCB is bad
.
YE
S
Th
is
bo
ard
h
a
s b
ig
p
ro
b
lem
b
ecau
se Main
ch
ip(BCM3
553)
hav
e s
o
me
trouble
s
.
A
fte
r c
h
ec
k
ing thoro
ugh
ly
all pa
th
onc
e
ag
ai
n,
Yo
u
sh
ou
ld decid
e to
rep
lace BCM3
553 o
r n
o
t.
RGB_PC doesnt display
Ch
eck JP7
029,JP7030.
Can
y
o
u
see t
h
e n
o
rmal
w
a
v
e
fo
rm?
YE
S
NO
JK70
5 ma
y
h
a
v
e
p
ro
b
lem. R
e
p
lace th
is Jack.
YE
S
Ch
eck th
e R756, R759 in
fro
n
t o
f BCM35
53.
Can
y
o
u
see t
h
e n
o
rmal
w
a
v
e
fo
rm?
NO
A
fte
r c
h
ec
k
the
pa
tte
rn be
tw
een
input
of
BCM35
53 an
d
JK705 ,
Yo
u
can
su
spect th
at PCB is bad
.
- 22 -
HDMI doesnt display
Check input c
onnect JK602.
Can
y
o
u
see t
h
e n
o
rmal
w
a
v
e
fo
rm?
Ch
eck DD
C c
o
mmu
n
ication
lin
es
(IC601 Pin5,6)
Ch
eck th
e in
pu
t o
f PI3HDMI341
A
R
T(IC600)
Th
is
sign
al is
TMDS.
Can
y
o
u
see t
h
e n
o
rmal
w
a
v
e
fo
rm?
YE
S
YE
S
NO
JK60
2 ma
y
h
a
v
e
p
ro
b
lem. R
e
p
lace th
is Jack.
Ch
eck th
e o
u
tp
u
t o
f
PI3HDMI341
A
R
T(IC600 ).
Can
y
o
u
see t
h
e n
o
rmal
w
a
v
e
fo
rm?
YE
S
Ch
eck th
e in
pu
t an
d
o
u
tpu
t
o
f BCM3553.
Esp
ecially
y
o
u
sh
o
u
ld
ch
ec
k
The
H,V s
y
nc
and c
loc
k
.
Can
y
o
u
see t
h
e n
o
rmal
w
a
v
e
fo
rm?
YE
S
NO
NO
Af
te
r ch
ec
kin
g
th
e trace o
f
TMDS lin
es a
n
d
po
w
e
r o
f
PI3HDMI341
A
R
T, y
ou should decide to replace
PI3HDMI341
A
R
T or not
.
NO
YE
S
Th
is
bo
ard
h
a
s b
ig
p
ro
b
lem
b
ecau
se Main
ch
ip(BCM3
550)
hav
e s
o
me
trouble
s
.
A
fte
r c
h
ec
k
ing thoro
ugh
ly
all pa
th
onc
e
ag
ai
n,
Yo
u
sh
ou
ld decid
e to
rep
lace BCM3
550 o
r n
o
t.
Af
te
r
ch
ec
kin
g
th
e Po
w
e
r
of th
is ch
ip
, y
o
u
should decide
to replace this or not.
Af
te
r ch
ec
kin
g
th
e Po
w
e
r
of PI3HDMI341
A
R
T
y
ou should
decide to replace PI3HDMI341A
RT or
not.
YE
S
Ch
eck HD
CP co
mmu
n
ication
lin
es
(IC102 Pin5,6)
NO
A
fte
r
ch
ec
kin
g
th
e Po
w
e
r
of th
is ch
ip
, y
o
u
should decide
to replace this or not.
- 23 -
BLOCK DIAGRAM
- 24 -
EXPLODED VIEW
300
500
700
510
120
120
121
900
910
530
520
600
610
810
820
400
200
800
802
801
803
804
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