Main Pcb Trouble Diagnosis; Video & Jack Pcb Trouble Diagnosis - Daewoo DP-42SM Service Manual

8. Main PCB Trouble Diagnosis

[NOTE] See II. PARTS of MODULE of this service manual for the trouble diagnosises concerned
to MODULE with exception of VIDEO, JACK and POWER parts.
8-1. VIDEO & JACK PCB Trouble Diagnosis
1. Common checking process when No signal or No raster
Check start
Does "No signal" screen
appear?
Is the signal input Jack
correctly connected?
Does input source
(AV device)operate?
Is input selection in used
mode?
Exchange Video or Jack PCB
2. When No VIDEO (COMPOSITE, S-VIDEO, Y Cb Cr) signal on screen
(1) Input PC or DTV signal and see if PC or DTV signals shown on screen.
If no signal, check TP DCLK, DHS and DVS signal.
If DCLK, DHS and DVS signal do not appear, VIDEO PCB has a trouble.
(2) When Y Cb Cr input : Check 16th pin of P502.
Y
N
Y
N
Check the connection of
Jack(PDP or AV devide)
Y
N
Operate AV device
Y
N
Confirm input
selection
Y
COMPOSITE Input : Check TP Vin.
Is there a weak
discharge on the
screen?
Y
Is P604 correctly
connected?
Y
Is DVS, DHS, DCLK of
Video PCB normal?
Y
1. Check other PCBs (CONTROLLER,
Y/Z-SUS, CONNECTION...)
2. Reassemble or change P31
-28-
1. Confirm AC connection
N
2. Confirm Power S/W ON
3. Check other PCBs
(Refer to II. Parts of Module)
N
Check P31
N
Exchange Video PCB