Daewoo DP-42SM Service Manual page 31

Main PCB Trouble Diagnosis
4. When PC signal do not appear on screen
(1) Input DTV or VIDEO signal and see if DTV or VIDEO signals shown on screen.
-->If no signal, check TP DCLKB, DHS and DVS.
-->If DCLKB, DHS and DVS signal do not appear, JACK PCB has a trouble.
(2) Check 1st PIN (V SYNC), 2nd PIN (H SYNC) of P502 (when 800X600).
--> If above signal do not appear, JACK PCB has a trouble.
(3) Check TP GHS, GVS and GCLK.
--> If GHS, GVS and GCLK signal do not appear, JACK PCB has a trouble.
5. When No Sound
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