Sharp LC-22SV2E (serv.man8) Service Manual ▷ View online
20
LC-22SV2E
TROUBLE SHOOTING TABLE
No picture, No sound
Check all the settings microprocessor's adjust process menu.
Do F3701 and F3702
function?
Are T701's secondary
outputs, +32V, +9V,
+5V and -8V normal?
Remove F3701 and F3702
and check the load side.
Is there short-circuiting?
Is there short-circuiting of
T3701 primary side periphery,
Q3702, Q3711 and P3706?
Replace F3701 and F3702.
Check T3701's secondary
side periphery.
Check T701's secondary
load.
Yes
No
Yes
Yes
Yes
No
No
No
Check all connection of each unit. (Refer to overall wiring diagram.)
Check T701's primary side
periphery.
Check T3701's primary side
periphery, Q3711 and their
perpheral parts.
Fluorecent lamp failure to light up
Does F3701, F3702, F6551,
F6552, F6553 and F6554
function?
Is the pin (31) of IC4561 in
the "H" state?
Are the Q6553, Q6556, Q6559
and Q6562 short-circuiting?
Is T6551~T6557's primary
oscillator waveform normal?
Yes
Yes
No
No
No
Yes
Replace the fluorescent
lamp with new one and
check again.
Yes
Check the OFL line, IC14561
and their peripheral parts.
Check Q6553, Q6556,
Q6559, Q6562 and their
peripheral parts.
Check Q6551, Q6554, Q6557,
Q6560, Q6552, Q6555,
Q6558, Q6561 and
connection cable.
21
LC-22SV2E
TROUBLE SHOOTING TABLE
(Continued)
No picture
Check all the settings microprocessor's adjust process menu.
Is in/output of
IC801 normal?
Is in/output of
IC4101 normal?
Check IC801
and its
peripheral parts.
Check IC4101
and its
peripheral parts.
Check IC3402
and its
peripheral parts.
Check IC801,
AV1 line and its
peripheral parts.
Is in/out of
IC4561 normal?
Yes
Yes
No
No
No picture
at all
Check IC4561
and its
peripheral parts.
No
Check LCD
panel voltages
and waveform.
Yes
Is in/output of
IC3402 normal?
Is input at pin
(73) of IC801
normal?
Yes
No
No
No TV and
VIDEO 2
output
Is voltages at
pins (6), (7)
and (18) of
W14
tuner normal?
Is output at pin
(13) of tuner
normal?
Check the
power line.
Check tuner
and its
peripheral parts.
Is input at pin
(3) of IC3402
normal?
Is the pins (2)
and (4) of
IC3402 at "H"
and "L" state?
Yes
Yes
No
No
Yes
No
Yes
No TV output
Check the pins
(65) and (66) of
IC2001 at "H"
and "L" state.
No
Check the its
line.
Check IC3402
and its
peripheral parts.
Is input at pin
(1) of IC3402
normal?
Is the pins (2)
and (4) of
IC3402 at "L"
state?
Check the its
line.
Check IC3402
and its
peripheral parts.
Check the pins
(65) and (66) of
IC2001 at "L"
state.
Yes
No
No
Yes
No VIDEO 2
output
22
LC-22SV2E
TROUBLE SHOOTING TABLE
(Continued)
No picture
Check all the settings microprocessor's adjust process menu.
Is input at pin
(74) of IC801
normal?
Check the AV1
line (SCART
INPUT) and
their peripheral
parts.
Check the
SY-line, SC-line
and their
peripheral parts.
No
No VIDEO 1
output
Is input at pins
(71) and (72) of
IC801 normal?
No
No S-VIDEO
(VIDEO 1)
output
Is input at pin
(70) of IC801
normal?
Check the
V2VO line and
their
peripheral parts.
No
No line
output
Is input at pins
(96)~(107),
(110)~(121)
and (132)~(143)
of IC4101
normal?
Is output at pins
(57)~(60) of
IC1601
normal?
Check IC4101
and its
peripheral parts.
Check the its
line. (V2V0)
Check the its
line.
Is output at pin
(21) of IC1601
normal?
No
Yes
Yes
No
No
No TELETEXT
output
Check IC1601
and its
peripheral parts.
Yes
23
LC-22SV2E
TROUBLE SHOOTING TABLE
(Continued)
No picture
Check all the settings microprocessor's adjust process menu.
Is source GND
normal?
Is CSCOM
waveform
normal?
Check FB4901,
FB4902 and its
peripheral parts.
Check IC4702,
IC4701, Q4701
and their
peripheral parts.
Check FB4562
and its
peripheral parts.
Yes
No
No
Becomes
dark
No
Time passes,
becomes
dark
Is gate GND
normal?
Is gate clock
(GCK) normal?
Check FL4572,
R4582 and gate
aray peripheral
parts.
Yes
No
Check IC4568
and its
peripheral parts.
No
Is VEE-6V being
outputted?
Is VGH+34V
being
outputted?
Check IC4565
and its
peripheral parts.
Yes
No
Is GSP
waveform
normal?
Check R4578
and its
peripheral parts.
Yes
No
Becomes
white.
Is VSH+3.3V
being
outputted?
Is source clock
normal?
Check IC4713
and its
peripheral parts.
Check R4563,
IC4561 and
their peripheral
parts.
Check IC4907
and gate aray
peripheral parts.
Is output of LBR
normal?
Yes
Yes
No
No
No
Vertical line
output
Display
