No Picture - Sanyo PLC-WXU700A Service Manual

Troubleshooting

No Picture

Check following steps.
No picture with all of
input sources
No
No picture with HdMI
input source only
No
No picture with PC input
source only
No
No picture with video
input sources
Yes
Check signal processing stage and LCD driving stage;
C heck RGB S&H signals at test points TP35B, TP35G, TP35R.
C heck power supply circuit 15.5V and peripheral circuit.
C heck ICs IC501, IC531, IC561, IC401, IC301 and peripheral circuits.
Yes
Check HDMI interface stage;
C heck IC7001<HDMI Driver> and peripheral circuit.
Yes
Check PC source stage;
Computer source
Check RGB signals on PC1.
R1 signal is applied to pin 7 of IC01<AD Conventer>, G1 signal is
applied to pin 1 and B1 signal is applied to pin 19 of IC 01.
HV sync signals are applied to pins 33 and 44 of IC01<AD
Conventer> as the HS1 and VS1 signals.
Check RGB signals on PC .
R signal is applied to pin  of IC01<AD Conventer>, G signal is
applied to pin 4 and B signal is applied to pin 8 of IC 01.
HV sync signals are applied to pins 34 and 45 of IC01<AD
Conventer> as the HS and VS signals.
Check AV source selecting and decoding stage;
S-Video source
Check S-video signal (Y/C).
S -C signal is applied to pin 108 of IC301<System Control>, and S-Y
signal is applied on pin 318 of IC301.
S_SW signal (S-VIDEO:L) is input to pin 36 of IC301<System Control>.
Yes
Composite video source
Check composite video signal (Video).
T he composite video signal is applied to pins 109 of IC301 <System
Control>.
Component source
Check component signal(YCbCr).
SOG1 signal is applied to pin 315 of IC301<System Control>, Y signal
is applied to pin 106 of IC301<System Control>, Cr signal is applied
to pin 14 of IC301<System Control> and Cb signal is applied to pin
15 of IC301<System Control>.
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