Sharp Aquos LC 26GD4U, Service Manual

Page: 43 / 207

43
LC-26GD4U
TROUBLE SHOOTING TABLE
(Continued)
YES YES YES YES YES
YES YES
NO NO NO NO
YES YES
YES
YES YES YES
NO NO NO NO NO NO NO NO
<Signals>
No picture (1)
<Composite video signal> input
Exter
nal input in troub
le <INPUT 1>
Is INPUT 1 selected in the input select men
u
screen?
Is composite video signal detection functioning nor
m
ally? Chec
k betw
een pin
(11) of J1101 and pin (9) of IC1102. Chec
k betw
een pin (8) of J1101 and pin (65)
of IC3800. Select INPUT 1 and the input signal in the input select men
u
screen.
If signal name is g
ra
y
and not selectab
le in
the men
u
screen
Is composite video signal detection functioning nor
m
ally? Chec
k betw
een pin
(10) of J1101 and pin (11) of IC1102. Chec
k betw
een pin (9) of J1101 and pin (71)
of IC3800. Chec
k
IC3800 (A
V SWITCH) and the
per
ipher
al circuits
.
Select INPUT 2 and the input signal in the input select men
u
screen.
If signal name is g
ra
y
and not selectab
le in
the men
u
screen
Is there video signal input at pin (65) of IC3800 (A
V SWITCH)?
Is there video signal input at pin (85) of IC400 (MAIN
VIDEO CHR
OMA)?
Are there digital video signal outputs at pins (43), (44), (46)~(49), (54), (55) and (58) of IC400?
Are there digital video signal inputs at pins (53), (54), (57)~(60), (51), (52) (RE0-7), pins(63)~(68), (61), (62) (GE0-7), pin
s (73)~(78), (69),
(70) (BE0-7), pins (81)~(86), (79), (80) (R
O0-7), pins (91)~(96), (89), (90) (GO0-7), pins (99), (100), (1), (2), (5), (6), (97
), (98) (BO0-7), and
pins (7)~(10) (HSYNC
,
VSYNC
, DE, CLKIN) of IC3201 (L
VDS
TRANSMITTER)?
Are there digital video signal outputs at pins (49)(T
A1
–
), (48)(T
A1+), (47)(TB1
–
), (46)(TB1+), (44)(TC1
–
), (43)(TC1+),(41)(TCLK
–
),
(42)(TCLK+), (40)(TD1
–
), (39)(TD1+), (37)(T
A2
–
), (36)(T
A2+), (35)(TB2
–
), (34)(TB2+), (32)(TC2
–
), (31)(TC2+), (30)(TCLK2
–
),(29)(TCLK2+),
(28)(TD2
–
), and (27)(TD2+) of IC3201?
Is INPUT 2 selected in the input select men
u
screen? Is there video signal input at pin (71) of IC3800 (A
V SWITCH)?
Are there MAIN
VIDEO signal output at pin (60) of IC3800 and SUB
VIDEO signal output at pin (56)?
Are there video signal input at pin (2) of IC401 (MAIN L.P
.F
.) and at pin (2) of IC501 (SUB L.P
.F
.)?
Exter
nal input in troub
le <INPUT 2>
Chec
k betw
een IC3800 and IC401/IC501.
<MAIN System>
<SUB System>
Chec
k
betw
een IC401 and IC400.
Is there video signal input at pin (85) of IC500 (SUB
VIDEO CHR
OMA)?
Chec
k
betw
een IC501 and IC500.
Chec
k IC 400 (MAIN
VIDEO CHR
OMA)
and the per
ipher
al circuits
.
Are there digital video signal outputs at pins (43), (44), (46)~(49), (54), (55) and (58) of IC500?
Chec
k
IC500 (SUB
VIDEO CHR
OMA) and
the per
ipher
al circuits
.
Replace the main PWB
, or chec
k
betw
een
IC400/IC500 and IC3201. Chec
k IC3201 (L
VDS
TRANSMITTER) and
the per
ipher
al circuits
.
Chec
k the LCD CONTR
OL PWB
.