Samsung PN59D8000 Nothing After Move to Basement

[deeMatrix]

Originally Posted by Diah

from the first photo it tell at which condition the Power boards, sockets got yellowish / dry then how about its soldering. i would suggest take out boards one after one and clean sockets / cable end to end and inspect the soldering .. i dont believe set will got defect if you moved it from work condition to basement unless the environment at the basement caused am issue.

Thanks Diah for your input. I will try your suggestions. As an FYI, the basement has a dehumidifier and roughly around 50rh most of the time although there were a few days when it went up to 60rh before we ever turned the set on.

[dick_barton]

That level of humidity shoudn't be a problem.
As Diah says to stop working after being placed in storage for a few days is strange.
I have often repaired equipment which has been run for years and only every switched off into standby. After they have been powered down for a day or so for whatever reason, eg decorate the room or moving house they fail to power back up. This is more often due to electroytic capacitors failing.

[deeMatrix]

Originally Posted by dick_barton

That level of humidity shoudn't be a problem.
As Diah says to stop working after being placed in storage for a few days is strange.
I have often repaired equipment which has been run for years and only every switched off into standby. After they have been powered down for a day or so for whatever reason, eg decorate the room or moving house they fail to power back up. This is more often due to electroytic capacitors failing.

This is interesting. In light of what you have seen is this often on the power supply board (SMPS in this case)? Another thread I saw on the site talked about a similar problem back in 2017 which turned out to be partially the SMPS, at least for the power up aspect so thinking ordering and replacing that may be worth a shot. Not sure if the logic board also makes sense but do get the 3.3v on VS_On initially which the logic board initiates and the green LED light so likely just start with the power board. Thoughts on this approach?

[dick_barton]

Originally Posted by deeMatrix

I then went and tested all the various voltages as rated on the various connectors which were spot on, except for the VA and VS which were very low and the VS_On which didn't register any voltage with logic board not connected. When the logic board was connected the VS_On goes up to 3.3V once powered on as it's suppose to but then quickly goes back down to 0V as though was shut down or something.

From another thread on this site.

3. If the PS_ON signal changes to Low, the Main SMPS supplies power to the Main Board and Logic Board, and Va and Vg power
is supplied to the DC-DC SMPS.
4. If the VS_ON signal from the Logic Board changes from Low to High, the Main SMPS supplies VS power to the X and Y Main
Board through the DC-DC SMPS, and the screen displays a picture on it.

It looks as though if the above is applicable to your set then the 3.3V from the logic board should stay high in order to maintain Va & Vs.
Have you checked that the logic board 3.3V output is not the problem?

Someone recently replaced their logic board and that brought up the supplies. I'll see if I can find the thread.

Edit
Here it is https://www.badcaps.net/forum/showth...ht=logic+board

[deeMatrix]

Originally Posted by dick_barton

From another thread on this site.


It looks as though if the above is applicable to your set then the 3.3V from the logic board should stay high in order to maintain Va & Vs.
Have you checked that the logic board 3.3V output is not the problem?

Someone recently replaced their logic board and that brought up the supplies. I'll see if I can find the thread.

Edit
Here it is https://www.badcaps.net/forum/showth...ht=logic+board

Hi dick_barton, Happy Thanksgiving. When I power set on PS_On goes from ~3.3v down to ~.2v and VS_On goes up to ~3.3v but quickly goes back down to 0v as though it was shut down or something (potentially by logic board)? BTW, I ordered the SMPS so we'll see what happens as had green blinking LED on logic board so figured start with the SPMS first. Can always return and get the logic board which is actually a lot less expensive if turns out that SMPS is not the issue.

[deeMatrix]

Originally Posted by deeMatrix

Hi dick_barton, Happy Thanksgiving. When I power set on PS_On goes from ~3.3v down to ~.2v and VS_On goes up to ~3.3v but quickly goes back down to 0v as though it was shut down or something (potentially by logic board)? BTW, I ordered the SMPS so we'll see what happens as had green blinking LED on logic board so figured start with the SPMS first. Can always return and get the logic board which is actually a lot less expensive if turns out that SMPS is not the issue.

So received and replaced the SMPS and TV is now fully functioning! Thanks dick_barton for your assistance and a big shout out to the community for a job well done!

[dick_barton]

Glad that you got there in the end. Happly viewing.