Sharp Aquos LC-20B4M, Service Manual, Page: 19 / 82

19
LC-20B4M
TROUBLE SHOOTING TABLE
(Continued)
Chec
k all the settings on the microprocessor
’s adjust process men
u
.
Are inputs and outputs of IC801 as specified?
Does the DPS test patter
n
appear?
Does the video decoder test patter
n
appear?
Chec
k IC3401
and its per
ipher
al
par
ts
.
Chec
k
IC1201, its per
ipher
al
circuits and the LCD panel. Chec
k IC801
and its per
ipher
al
circuits
.
Are inputs and outputs of IC3401 as specified?
Chec
k
IC3401 and its per
ipher
al
par
ts
.
Is input at Pin (73) of IC801 as specified?
Chec
k IC801,
A
V1 line and
their per
ipher
al
par
ts
.
Are inputs and outputs of Q1602, Q1604 and Q1606 as specified?
Chec
k Q1602,
Q1604, Q1606 and its per
ipher
al
par
ts
.
Is output at pins (57)~(59) of IC1601 nor
mal?
Chec
k the R,
G and B line
.
Is input at pin (21) of IC1601 nor
mal?
Chec
k V2V0
line and its per
ipher
al
par
ts
.
Chec
k IC1601
and its per
ipher
al
par
ts
.
Are inputs at Pins (71) and (72) of IC801 as specified?
Chec
k
SC3405, SY line
, SC line
and per
ipher
al
par
ts
.
Is input at Pins (4), (5), (6) and (75) of IC801 as specified?
Chec
k J3404,
D
VD-Y line
,
PB line
, PR
line and per
ipher
al
par
ts
.
Are v
oltages
at Pins (6), (7) and (9) of tuner as specified?
Chec
k the
po
w
er line
.
Is output at Pin (19) of tuner as specified?
Chec
k the
tuner and its per
ipher
al
par
ts
.
Is input at Pin (16) of IC3401 as specified?
Chec
k the
line in question.
Chec
k IC3401
and its per
ipher
al
par
ts
.
Are Pins (3) of IC3401 at H?
Are Pins (48) of IC2001 at H?
Chec
k the
line in question.
No picture
No picture at all
No VIDEO 1 or 2 output
No TELE TEXT output
No S VIDEO output
No COMPONENT output
No TV output
Yes
No
Yes
No No
No
Yes
No
No
Yes
Yes
No
No
Yes
No
No
Yes
No
Yes
No No
Yes Yes
No
Yes