Eiki LC-XB42, Руководство по обслуживанию

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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 TP_B1, TP_G1, TP_R1.
Check power supply circuit 15.5V and peripheral circuit.
Check ICs IC501, IC531, IC561, IC2501, IC2531, IC2561, 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/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
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 410, 408, 411 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
Yes
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