Sanyo PLC-XU111, Service Manual

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Troubleshooting
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, IC501, IC531, IC561, IC401,
IC301 and peripheral circuits.
Check DVI interface stage;
Check IC8001<DVI I/F> and peripheral circuit.
No picture with Pc1
[digital] input source
only
No picture with Pc2
[Analog]input source
only
Check PC1/PC-switching stage;
Check IC501<PC1/PC-SW> and peripheral circuit.
PC1/PC_SW signal (PC: H) is output from pin 348 of
IC301<Scaler> and applied to pin 6 of IC501.
PC1:L, PC:H
Check PC/AV source selecting stage and processing stage;
Check IC501<PC1/PC_SW> and IC301<Scaler> and peripheral
circuit.
No picture with all of
computer input sources
Yes
Yes
Yes
No
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 65 of IC301<Scaler>, and S-Y signal is
applied on pin 64 of IC301.
S_SW signal (S-VIDEO:L) is input to pin 67 of IC301<Scaler>.
Component video source
Check component signal (Y/Cr,Pr/Cb,Pb).
The component signals are applied to pins 410, 408, 411 of IC301
<Scaler>.
Composite video source
Check composite video signal (Video).
The composite video signal is applied to pins 6 of IC301 <Scaler>.
No picture with video
input sources
Yes
Check PC1/PC-switching stage;
Check IC501<PC1/PC-SW> and peripheral circuit.
PC1/PC_SW signal (PC: H) is output from pin 348 of
IC301<Scaler> and applied to pin 6 of IC501.
PC1:L, PC:H
No picture with Pc1
[Analog] input source
only
No
Yes