Hello Everyone, I been reader here for quite a wwhile and managed to fix several tvs with suggestions from here. This time I am stumped. I am working on Westinghouse DWM55F1G1 that has sound and backlight but blank screen. Upon taking it apart I measured voltage going into tcon and 12V was missing. I looked down tcon cable toward main/power supply board and noticed that little three legged small part(diode???) is burned and bubbled right next to tcon cable connector. I barely touched and it all crumbled. I had similar case where same thing happened with same tv brand and after jumping 12V onto tcon fuse picture came on and tv worked. Replacement main solved that previous problem.
This time I ordered replacement main/power supply and after everything was in place tv would only cycle and not come up. If I unplug tcon cable tv would start up and stay ON. This tv model does not have tcon board that is removable, it is integrated into screen strip and something there is shorted and shuts main board down. Short is on main strip where all big ICs are because when I disconnect ribbon going into other half of screen it still shorts out. I read about possibly tiny capacitor being shorted but there is quite a lot of them. I tested all little caps brown and black for shorts like this, with multimeter in diode mode and found none that are dead shorted across. They all beep same in diode mode- for millisecond and stop beeping. I would like you guys to direct me into which of them I would take off and see if it resolves short. I have capacitor tester also but i only tested tiny caps for dead shorts across in diode mode without removing. When in diode mode between tv chassis(grnd) and tcon fuse I get .160 . See last picture.
This time I ordered replacement main/power supply and after everything was in place tv would only cycle and not come up. If I unplug tcon cable tv would start up and stay ON. This tv model does not have tcon board that is removable, it is integrated into screen strip and something there is shorted and shuts main board down. Short is on main strip where all big ICs are because when I disconnect ribbon going into other half of screen it still shorts out. I read about possibly tiny capacitor being shorted but there is quite a lot of them. I tested all little caps brown and black for shorts like this, with multimeter in diode mode and found none that are dead shorted across. They all beep same in diode mode- for millisecond and stop beeping. I would like you guys to direct me into which of them I would take off and see if it resolves short. I have capacitor tester also but i only tested tiny caps for dead shorts across in diode mode without removing. When in diode mode between tv chassis(grnd) and tcon fuse I get .160 . See last picture.
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