Canon D78-5382, Руководство по обслуживанию

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1.2 No Picture
Check following steps.
Part 4: Troubleshooting
4-3
No picture with all of
input sources
Check signal processing stage and LCD driving stage;
Check RGB S&H signals at test points TP501B,
TP502B, TP503G, TP504G, TP505R, TP506R.
Check PSIG signals at test points TP3501 and TP3531.
Check power supply circuit 15.5V SWD and peripheral
circuit.
Check ICs IC501, IC531, IC561, IC1501, IC1531,
IC1561, IC3501, IC3531, IC401, IC301 and peripheral
circuits.
Check DVI interface stage;
Check DVI receiver, IC8001, buffer ICs IC8051, IC8061,
IC8071 and peripheral circuit.
DVI switch signal, DPC_ON (DVI: L), is output from pin
15 of IC1804 and applied to IC5331 through Q5331.
No picture with PC1[DVI
digital] input source
No picture with PC1 [DVI
analog] input source
Check PC source selecting stage;
Check IC3061, RGB buffer, and peripheral circuit on the
DVI board.
Check IC1201, PC1/PC2 RGB SW, and IC5311,
PC1/PC2 SYNC-SW and peripheral circuit.
PC1/PC2_SW5 signal (PC1: L) is applied on pin 22 of
IC1201, and pins 9, 11 of IC5311, and output from pin
16 of IC1813 through IC1351, buffer IC.
Check PC source selecting stage;
Check IC221, Sync sw, and peripheral circuit on the AV
board. Check MNTOUT_SW5 signal (PC2-Monitor-
Out:H) is applied on pin 1 of IC201 and pins 9, 10, 11 of
IC221 on the AV board and output from pin17 of IC1813
through IC1351, buffer IC.
Check IC3101, Video decoder, and IC7201, matrix and
peripheral circuit.
Check IC1201, PC1/PC2 RGB SW, and IC5311,
PC1/PC2 SYNC-SW and peripheral circuit.
PC1/PC2_SW5 signal (PC1: L) is applied on pin 22 of
IC1201, and pins 9, 11 of IC5311, and output from pin
16 of IC1813 through IC1351, buffer IC.
No picture with PC2 [VGA
analog] input source
Yes
Yes
Yes
Yes
No
No
No
No
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