Sanyo PLC-XL50, Service Manual

Page: 76 / 126

No Picture
No picture with all of
input sources
Check signal processing stage and LCD driving stage;
Check RGB S&H signals at test points TP35B, TP35G, TP35R1.
Check power supply circuit 15.5V and peripheral circuit.
Check ICs IC501, IC531, IC561, IC2501, IC2531, IC2561, IC401,
IC301 and peripheral circuits.
No picture with PC2
[Analog]input source
only
Check PC1/PC2-switching stage;
Check IC5201<PC1/PC2-SW> and peripheral circuit.
PC1/PC2_SW signal (PC2: H) is output from pin 348 of
IC301<Scaler> and applied to pin 26 of IC5201.
PC1:L, PC2:H
Check PC/AV source selecting stage and processing stage;
Check IC5201<PC1/PC2_SW> and IC301<Scaler> and peripheral
circuit.
No picture with all of
computer input sources
Yes
Yes
Yes
No
No
No
Check following steps.
Check AV source selecting and decoding stage;
S-Video source
Check S-video signal (Y/C).
S-C signal is applied to pin 265 of IC301<Scaler>, and S-Y signal is
applied on pin 264 of IC301.
S_SW signal (S-VIDEO:L) is input to pin 267 of IC301<Scaler>.
Component video source
Check component signal (Y/Cr,Pr/Cb,Pb).
The component signals are applied to pins 256, 78, 172 of IC301
<Scaler>.
Composite video source
Check composite video signal (Video).
The composite video signal is applied to pins 262 of IC301 <Scaler>.
No picture with video
input sources
Check PC1/PC2-switching stage;
Check IC5201<PC1/PC2-SW> and peripheral circuit.
PC1/PC2_SW signal (PC2: H) is output from pin 348 of
IC301<Scaler> and applied to pin 26 of IC5201.
PC1:L, PC2:H
No picture with PC1
[Analog] input source
only
No
Yes
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Troubleshooting