samsung un82mu8000fxza image disappearing

[superg]

I went to client's office to look at this tv. I didn't open because I don't know where to start. It works for a while and then the picture disappears.The back light stays on and there is no sound or picture. I tested it on youtube.

[dick_barton]

Re: samsung un82mu8000fxza image disappearing

That is a large set and I would be hesitant in opening it up.
If you can remove the back cover and cool the heatsink over the BGA chip to see if it stays on longer.

[brucetv]

Re: samsung un82mu8000fxza image disappearing

We had one of these beast's in 2 months ago and it turned out to be a bad Main Video board part #BN94-12552R. We had steady backlights and audio but no 12V on Tcon fuse F203. See if you have 12V on both sides of that fuse. If you do turn tv off and disconnect one ribbon cable on the tcon and turn on and see if you see the Samsung Logo screen pull up. This beast has four. Try all four one by one and see if the Samsung logo pull up at all. If the tv does boot up properly with one of those ribbons disconnected you may have a short on the lower driver board for that section. It's usually a bad cap or two on that driver board and a pain to find the short because they are in parallel so you have to remove one itty bitty cap at a time to find it. The MU series has been plagued with this problem.

[CapLeaker]

Re: samsung un82mu8000fxza image disappearing

probably a bga issue on the main IC on the main board.

[nomoresonys]

Re: samsung un82mu8000fxza image disappearing

Maybe try heating the mainboard and powerboard with a hairdryer when it fades out, see if it fades back in, heat the electrolytic capacitors first then move around from there.