Sharp Aquos LC 26D7U, Service Manual

Page: 53 / 214

53
LC-26D7U
LC-32D7U
LC-37D7U
TROUBLE SHOOTING TABLE
(Continued)
YES
YES YES
YES
NO NO NO
YES YES YES
YES YES
YES
NO NO
NO NO
NO NO NO NO NO
YES YES YES YES YES
NO NO
External input in trouble <
INPUT
-3>
Is INPUT
-3 selected in the input switchi
ng
menu screen?
Is there signal input
at each input pin of
IC3800 (A
V SWITCH)?
<Composite video si
gnal input>
Is there signal input at pin (3)? <S-video signal in
put>
Are there
Y
-signal input at pin (5)
and C-
signal input at pin
(7)?
Select INPUT
3 and the input signal in the
input switching men
u screen.
When it cannot be selected since the characters INPUT
-3 on the menu screen a
re gray
.
Is video signal detection fu
nctioning
normally? Check between pin (1
1) of
J1
106 and pin (12) of IC1
102.
Is S-video signal d
etection functioning
normally? Check between pin
(6) of J1
105
and pin (6) of IC3800.
Check between pin (8) of J1
106 and pin (3)
of IC3800.
Check between pins (3), (4) of
J1
105 and
pins (5), (7) of IC3800.
<Composite video si
gnal / S-video signal> i
nput
<Composite video si
gnal input>
Are there VIDEO signal output at pin (60)?
<S-video signal in
put>
Are there
Y
-signal output at pin (60) and C-signal outpu
t at pin (59) of IC3800?
<Composite video si
gnal input> Is video sign
al sent to pin (12) of
AV
_UNIT
connector (FD_SC
5701)?
<S-video signal in
put>
Are
Y
and C signals sent to pins (12) and (10) of
AV
_UNIT
connector
(FD_SC5701) respectivel
y?
Are digital video signals sent from pins (43), (44),
(46)-(49), (54), (55), (58) etc. of IC400?
No video output (2)
No video output when recei
ving UHF/VHF broadcasting
Is there video signal ou
tput at output pin
(17) of the tuner (TU1
101)?
Are there video signal inputs at pin (7) of IC1
1
03 (LEVEL
ADJ)?
Is tuner video signal su
pplied to pin (17) of
IC3800 (A
V SWITCH)?
Check or replace the tuner's peripheral circuits.
Are there inputs of level
adjustment control
signals at pin (6) of IC1
103
(LEVEL
ADJ) from pin (1) of
IC1
105?
Check IC1
105 (CONTROL) and the peripheral
circuits. Replace if necessary
.
No video output when receiving digital broadcasting
(4)
Is video signal from the di
gital unit
supplied to
A
V
_UNIT
connector (DA,
P1
105)?
Check the digital unit.
Is DTV video signal supplied to pin (15) of IC3800 (A
V SWITCH)?
Check between P1
105
and IC3800. (Q1
120,
Q1
122, etc.)
Check IC3800 (A
V SWITCH) and the
peripheral circuits. Check between IC3800 and SC5701. (Q3802, Q3810, etc.)
Are there digital video signal
inputs at pins (53), (54), (57)~(60), (51)
, (52) (RE0-7), pins(63)~(68), (61), (62) (GE0-7
), pins (73)~(78)
, (69), (70) (BE0-7
), pins
(81)~(86), (79), (80) (RO0-7), pins
(91)~(96), (89), (90) (GO0-7), pins
(99), (100), (1), (2), (5), (6), (97)
, (98) (BO0-7), an
d pins (7)~(10) (HSYN
C, 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)(T
B2–), (34)(TB2+), (32)(
TC2–), (31)(TC2+), (3
0)(TCLK2–),(29)(TCLK2+), (28)(TD2–), and (27)(TD2+) of IC3201?
Check IC400 and its peripheral circuits.
<Composite video
signal input> Is video signal suppl
ied to pin (85) of IC400 (3D-YC &
CHROMA) through L.P
.F
. consisting of Q41
1
and Q412?
<S-video signal input>
Are
Y
and C video signals supplied
to pins (85) and (90) of IC400 (3D-YC & CHROMA) through L.P
.F
. consisting of Q41
1 and Q412 and L.P
.F
.
consisting of Q415 and Q416 respectively?
Check between IC3800 and IC400. (Q3802, Q3810, Q41
1, Q412, etc.)/
(Q3801, Q381
1, Q415, Q416, etc.)
<Composite video
signal input> Is video signal sent
to pin (22) of MAIN_UNIT
connector (FD_SC3201)?
<S-video signal input>
Are
Y
and C signals sent to pins (22) and (24) of MAIN_UNIT
connector (FD_SC3201) respectively?
Check the FFC harne
ss "FD".
Replace the main PWB, or check between IC400 and IC3201. Check IC3201 (L
VDS
TRANSMITTER)
and
the peripheral circuits.
Check the LCD CONTRO
L P
WB.