Sharp LC-20A2M, Service Manual

Page: 9 / 40

9
LC-20A2M
TROUBLE SHOOTING TABLE
No picture at all
Yes
No
Are inputs and outputs of IC802 as specified?
Chec
k all the settings on the microprocessor’
s
adjust process men
u.
No picture
Chec
k IC802
and its per
ipher
al
par
ts
.
Yes
No
Are inputs and outputs of IC1201 as specified?
Chec
k
IC1201 and its per
ipher
al
par
ts
.
Chec
k LCD
panel v
o
ltage
and wav
e
fo
rm
.
No TV
and
VIDEO 1 output
Yes
No
Are inputs and outputs of IC402 as specified?
Chec
k IC402
and its per
ipher
al
par
ts
.
No
Is input at pin (73) of IC802 as specified?
Chec
k IC802,
A
V1 line and
their per
ipher
al
par
ts
.
No TV output
Yes
No
Are v
o
ltages
at pins (6), (7) and (9) of tuner as specified?
Chec
k the
po
w
e
r line
.
Yes
No
Is output at pin (19) of tuner as specified?
Chec
k the
tuner and its per
ipher
al
par
ts
.
No
Is input at pin (1) of IC402 as specified?
Chec
k the
line in question.
Yes
Chec
k IC402
and its per
ipher
al
par
ts
.
Yes
No
Are pins (2) and (4) of IC402 at
“H”
and “L
”
respectiv
ely?
Are pins (65) and (66) of IC2001 at
“H”
and “L
”
respectiv
ely?
No VIDEO 1 output
Yes
No
Is input at pin (1) of IC402 as specified?
Chec
k the
line in question.
Yes
No
Are pins (2) and (4) of IC402 both at “L
”?
No VIDEO 2 output
No
Is input at pin (74) of IC802 as specified? Chec
k
J3403,
A
V2 line and
their per
ipher
al
par
ts
.
No S VIDEO output
No
Are inputs at pins (71) and (72) of IC802 as specified?
Chec
k
SC3301, SY line
, SC line
and per
ipher
a
l
par
ts
.
No COMPONENT output
No
Is input at pins (4), (5), (6) and (75) of IC802 as specified?
Check J3405, DVD-Y
line,
CB line, CR line and peripheral parts.
Are pins (65) and (66) of IC2001 both at “L
”?
Chec
k IC402
and its per
ipher
al
par
ts
.
Yes
Chec
k the
line in question.
Yes
Chec
k the
line in question.