Samsung PN51D7000 Plasma turning off and on

[FIeury]

Ok, so my 2011 Samsung plasma is turning itself off and then immediately back on sometimes. It only does it in the first 20-30 minutes that the TV is started. If I don't leave the TV off for a couple hours its fine. Its almost like once the TV heats up its perfect. Sometimes it will do it once in that first 30 minutes. Sometimes 5. I took the back off and looked at the caps. They all looked ok. None were bubbled, cracked, or leaking. Not sure what the problem is. Any help would be awesome. Thanks

[ReeceyBurger123]

Re: Samsung PN51D7000 Plasma turning off and on

Check for cold solder joints on the Psu. Also upload pictures of the boards as well.

[FIeury]

Re: Samsung PN51D7000 Plasma turning off and on

http://imgur.com/a/9GyUS

There's a couple pictures of the power board. Still not sure qhat the problem is. Tv just clicks off and then on. Picture is fine. No distortion or anything. Its been happening for about 2 weeks. I do remember on one occasion it clicked off/on a few times rapidly and didn't come back until I unplugged it.

What makes me think its the power board is because I unplugged the connector that goes to the Main boards and I could still hear the TV clicking On/Off.

[bp805]

Re: Samsung PN51D7000 Plasma turning off and on

FIeury,

I have the exact same tv with the exact same problem. My power supply board doesnt have any busted caps that I can see. I was thinking of just replacing the power supply board, but dont want to do that in case there is something else. I have read other opinions that it could be the main board instead? But I dont know how to test either one to find out which one is bad to know which to replace. Did you have any luck repairing your TV?

ReeceyBurger123 - If I can upload pictures, are you able to determine from the pics what may be wrong? Thanks!

[bp805]

Re: Samsung PN51D7000 Plasma turning off and on

I tried to unplug various boards one at a time and turn the TV on to see if the power cycling issue stopped. Here are my results:

-Unplugged the main board from the power supply: TV would not turn on.
-Unplugged the y-main board from the power supply: TV turns on, no picture, and still power cycles on/off after about 45 seconds.
-Unplugged the logic board from the power supply: TV turns on, no picture, and still power cycles on/off after about 45 seconds.
-Unplugged the cables leading from the main board to the two black boxes at the bottom of the tv, and also the large horizontal board that is concealed behind the chassis at the bottom of the TV: TV turns on, with picture, still power cycles on/off after about 90 seconds.

Doing all this leads me to believe that it is the power supply board, but I really dont know.

Can anyone chime in and help me out? I can post pictures of internals if needed. Also have a voltage meter I can use if needed, but not too savvy on how to use it. Thanks for any help that can be provided!

[mnm415]

Re: Samsung PN51D7000 Plasma turning off and on

Hi there! Sorry, just found your post. Has there been any success in fixing the power cycling? I am finding the same scenario that you have. I think it is different from the one most found online (power on/off after Samsung logo comes on).

Hesitant on pulling the trigger and buying a "new" main board, as you can get some great deals now at Costco on similar sized LED tvs instead.

[freakaftr8]

Re: Samsung PN51D7000 Plasma turning off and on

Heat up the chips with the 25 or so pins on each side. These are NVRAM. Seemed to cure mine a few years back. Still working today

[mnm415]

Re: Samsung PN51D7000 Plasma turning off and on

Hey freakaftr8 - Thanks for your reply. Which board is this for? The main board? Logic board?

[freakaftr8]

Re: Samsung PN51D7000 Plasma turning off and on

Mainboard. I would perform this with the TV unplugged and heat the heck out of it then plug it in after you're done heating. Don't know why or how but somehow there was a blockage of data probably being received from the eeprom and heating it up wrote that parameter into the NV ram for boot then never had a problem yet.

I believe the I see you're looking for has a small white label stuck to it. Don't be afraid to apply some heat all over that area or in all over the board for that matter it's not going to hurt anything

[bp805]

Re: Samsung PN51D7000 Plasma turning off and on

mnm415- I believe what I did was replace the power supply board and it fixed all the problems.