Read LG 42LC4D (CHASSIS:LA73E) Service Manual online
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Check J5007 Pin3C
Can y
o
u see t
h
e n
o
rmal
w
av
e
form?
Check the input(Pin1 or Pin8) of
A
V
sw
itch(IC5003
). Pin
1
is fo
r
vi
deo1,Pin8
is
for v
ideo
2.
Can y
o
u see t
h
e n
o
rmal
w
av
e
form?
Check the output(Pin56) of
A
V
sw
itch(IC5003).
Can y
o
u see t
h
e n
o
rmal
w
av
e
form?
Check the input(Pin1) of
LP
F(IC4006).
Can y
o
u see t
h
e n
o
rmal
w
av
e
form?
YE
S
YE
S
YE
S
NO
J5007 may
hav
e problem. Replace this
Jack.
Check the output(Pin8)
of LPF(IC4006).
Can y
o
u see t
h
e n
o
rmal
w
av
e
form?
YE
S
Check the input(PinH26) of
BCM35
50(IC4
006).
Measu
re w
a
ve
form at C101
0
b
ecau
se it’s
more easy
to
check.
Can y
o
u see t
h
e n
o
rmal
w
av
e
form?
YE
S
NO
Af
te
r checking the Po
w
er
of
A
V
s
w
itch y
o
u
should decide
to replace
A
V
s
w
itch or
not.
NO
Af
te
r checking the Po
w
er
of
A
V
s
w
itch y
o
u
should decide
to replace
A
V
s
w
itch or
not.
NO
A
fte
r checking the Po
w
er
o
f LPF y
ou sho
u
ld
decide to replace LPF or not.
NO
A
fte
r checking the Po
w
er
o
f LPF y
ou sho
u
ld
decide to replace LPF or not.
YE
X
This board ha
s big
problem
because Main
chip(BCM3
550)
hav
e some trouble
s.
A
fter checking thorough
ly
all path
once
again,
You should decide to replace BCM3550 o
r not.
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