No Picture - Sanyo PLC-XU40 Service Manual

Troubleshooting

No Picture

Check following steps.
No picture with all of
input sources
No
No picture with PC1[DVI
digital] input source
No
No picture with PC1 [DVI
analog] input source
No
No picture with PC2 [VGA
analog] input source
No
No picture with all of
computer input sources
No
Go to next page
Yes
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.
Yes
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.
Yes
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.
Yes
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 cir-
cuit.
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.
Yes
Check PC/AV source selecting stage and processing stage;
Check IC5201, PC/AV RGB SW, and IC8201, A/D conversion and
peripheral circuit.
Check IC5321, IC5331, PC/AV Sync selection IC, and peripheral cir-
cuit.
PC/AV_SW5 signal (PC: H) is applied on pin 26 of IC5201, pin 2 of
IC5321, and pin 10 of IC5331, and output from pin 16 of IC1804
through IC1351, buffer IC.
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