Sharp AQUOS LC-37AD5E, Service Manual

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LC-37AD5E
4 – 9
No picture on the display (1)
No video output in all modes.
YES
Is LVDS video signal (LVDS_0N/0P-3N/3P) sent to pins (141)/
(140)-(129)/(128) of IC3002 (VCT), and is CLK signal (LVDS_CN/
CP) sent to pins (132)/(131)? NO Check IC3002 and its peripheral circuits.
YES
Is LVDS video signal (LVDS_0N/0P-3N/3P) sent to pins (20)/(19)-
(8)/(7) of connector (P2305), and is CLK signal (LVDS_CN/CP)
sent to pins (11)/(10)? NO Check the line between IC3002 and P2305.
YES
Is power (LCD5V) supplied to pins (28-31) of connector (P2305)? NO Check LCD5V_LINE and its peripheral circuits.
(Q1706, Q1704, etc.)
YES
Check the panel module.
<On input of the tuner (U/V)> No picture on the display (2)
No picture appears on LCD during the tuner (U/V) reception.
Checklist:
1) Is “INPUT SOURCE” button
on the remote control set up correctly?
•••
See the operation manual and set “INPUT SOURCE” to “TV”.
2) Is MENU-PICTURE-Contrast/Brightness set to “MIN”?
•••
Set it to an appropriate level.
3) Is ANT-CABLE disconnected or connected improperly?
•••
Connect it correctly as per the operation manual.
Is level of pins (15) and (14) of tuner (TU201) and pins (10) and
(11) of IC201 (IF-DEMOD) at H?
NO These are communications lines for control (I2C). Follow the
path and check whether they are forced to L (PULL_DOWN).
YES
Is the video signal (IF) sent from pin (17) of tuner (TU201)? NO Check the tuner (TU201) and peripheral circuits.
YES
Is video signal sent from pin (17) of IC201 (IF-DEMOD)? NO Check FL201 (SAW-FIL), IC201 and peripheral circuits.
YES
Is the video signal VIN1 (ATUNER-CVBS) sent to pin (191) of
lC3002 (VCT)? NO Check IC201 (IF-DEMOD), CONNECTOR (P201/SC2705) and
peripheral circuits. (Q204, etc.)
YES
Refer to “No video output in all modes”.