Sanyo DP50710 won't turn on.

[hardfahrer]

I have a Sanyo DP50710 that won't turn on. When i plug it in and hit the power button the green light comes on, relays click in the power supply and then it powers down and the green light goes off. Press power again and the same routine. Press it a third time, same thing. Beyond that, pressing the power button yields nothing. I have to unplug it and plug it back in to get the power supply clicking again. And so it goes. The unit does have a Panasonic sticker inside. I'm trying to isolate it to the board and not the component level.(i'm not that skilled) Any help in diagnosing the TV would be much appreciated. Where should i start?
Thanks.

[martino]

Re: Sanyo DP50710 won't turn on.

On the mainboard you see little white stars,with voltages written beside it.Those are test points. You will probably find the 13 volts for the audio driver to be very low.
pin 48 from the mainchip lcb7f will show low voltage I'm guessing(for it to do the shutdown.)
I would measure those test points as a start. Like I said,often it's the 13 volt for audio that goes bad.


Watch this video,it will help you greatly.Even tho your mainboard has a different 13 volt chip.
https://www.youtube.com/watch?v=KSYCn93pz6k

[hardfahrer]

Re: Sanyo DP50710 won't turn on.

Thanks so much for the info and video link. I was able to determine that the 13V audio test point is showing no voltage when I attempt to power up. All other test points would jump to the correct voltage and then the relay clicks and shuts power off. One pin was at 5V even with the supply off. After watching the video, it seemed he isolated the bad component (chip) and replaced it. The board in the video is very similar to the one in my Sanyo but when i looked, on my board, for the IC that he replaced there was an empty board. The board in my unit has a provision for the chip but it's not there. Does anyone know where or if there is a chip that regulates the 13V and where it is on the board or is it regulated with diodes and resistor circuits? I'm very much a novice at this stuff so thanks for the help.