Sanyo 1 122 356 20, Service Manual

Page: 47 / 94

-47-
Troubleshooting
No Picture
No picture with all of in-
put sources
Check signal processing stage and LCD driving stage;
Check RGB S&H signals at test points TPB1, TPG1, TPR1.
Check power supply circuit 15.5V and peripheral circuit.
Check ICs IC501, IC531, IC561, IC401, IC301 and peripheral
circuits.
Yes
No
check following steps.
Check each signal input stage;
Computer source
Check RGB signals.
R signal is applied to pin 8 of IC301<System Control>, G sig-
nal is applied to pin 60 and B signal is applied to pin 58 of IC
301.
HV sync signals are applied to pins 331 and 161 of IC301<System
Control> as the HS and VS signals.
S-Video source
Check S-video signal (Y/C).
S_CHROMA signal is applied to pin 65 of IC301<System Con-
trol>, and S_Y signal is applied on pin 64 of IC301.
Component video source
The component signals are applied to pins 8, 58, 409 of
IC301<System Control>.
Composite video source
Check composite video signal (Video).
The composite video signal is applied to pin 6 of IC301<System
Control>.