-84-
Troubleshooting
● No Picture
No picture with all of
input sources
Check signal processing stage and LCD driving stage;
Check RGB VID signals at test points TP35R, TP35G, TP35B.
Check power supply circuit 15.5V and peripheral circuit.
Check IC501, IC531, IC561, IC2501, IC2531, IC2561, IC401, IC4401, IC301
and peripheral circuits.
No picture with
HDMI (RGB digital)
input source
Go to next page
Yes
Yes
No
No
Check following steps.
SG: Digital RGB signals from IC8001 are sent to IC301, and the other signals
are A/D converted in IC8201 and sent to IC301. They are scaled in
IC301. After correcting for picture quality in IC4401 and IC401, they are
sent to IC501, IC531, IC561(sampling & holding, D/A conversion).
The panel driving signals are shifted the level up to 15V by IC2501,
IC2531, IC2561.
Sync: PW_HS/VS/CLK from IC301 to IC4401, DHS,DVS,DCLK from IC301 to
IC401
No picture with
COMPONENT1/2 (YCbCr)
input sources
Check Component source input stage;
Check IC5201, IC8201 and peripheral circuit.
Check sync signals at test points TPADHS and TPADVS.
Yes
No
SG: Component_1/2 signals are selected in IC5201, with COMP_1/2 signal
(Component_1 = Low). The selected signals are sent to IC8201. They
are A/D-converted in IC8201 and sent to IC301.
Sync: Y/Cb/Cr signals are sync-separated in IC8201, and ADHS and ADVS sig-
nals are sent to IC301.
Check HDMI (RGB digital) source input stage;
Check IC8001 and peripheral circuit.
Check sync signals SIHS and SIVS.
Check 5VHDMI power supply line.
SG: TMDS data signals are converted to RGB digital signals in IC8001, and
sent to IC301.
Receiving video content encrypted with HDCP(High-bandwidth Digital
Content Protection), IC8001 reads the HDCP keys and it allows the signal
processing.
Sync: SIHS and SIVS signals from IC8001 are sent to IC301.
SG: Description of visual signal flow
Sync: Description of sync signal flow