Samsung UN65JU6500FXZA ID03

[Crux85]

Hello Badcaps!

I've got a older Samsung TV that has been on the fritz for awhile, but finally stopped working altogether a few days ago. For a few months, it has randomly turned itself off after being turned on for about 15 minutes, the power light on the front would blink, and would turn itself back on after a few minutes and seem to work fine for the rest of the day/evening. The problem had slowly been getting worse until it has gotten to the point it won't power on at all. Disconnecting, letting it set for a few hours, and reconnecting the power doesn't change the behavior. It has always been connected to a surge protector, and nothing seemed excessively dusty/dirty.

I removed the back panel to see if there were any obvious signs of problems. No capacitors look bulged or popped. All connectors looked good. There are some heat marks on the power board, not scorched, but certainly noticeable.

Any guidance or troubleshooting advice would be greatly appreciated. Thanks!

[R_J]

Remove the power supply board and resolder all connections on the main transformer (TM801CS) and all components attached to the heatsinks like QM801CS and Q802CS, Also LP801CS & 802CS
Caps that can be weak are CM824, CM825 & CM826

[nomoresonys]

With tv unplugged from power, unhook cable from powerboard to mainboard on powerboard side, with it unhooked plug power cord into powerboard, see if backlights come on and stay on.

[R_J]

Remove the power supply board and resolder all connections on the main transformer (TM801CS) and all components attached to the heatsinks like QM801CS and Q802CS, Also LP801CS & 802CS
Caps that can be weak are CM824, CM825 & CM826

[Davi.p]

First thing to do is to test the PS board itself with dummy loads, if ok then probably bad solder under the CPU, needs reballing..

[Crux85]

Remove the power supply board and resolder all connections on the main transformer (TM801CS) and all components attached to the heatsinks like QM801CS and Q802CS, Also LP801CS & 802CS
Caps that can be weak are CM824, CM825 & CM826

I think this may be right on point. I missed a very gnarly looking solder on this component that could easily be shorting out. I'll resolder this evening and let you know the results.

[lotas]

Not here, but on the back side of the board... (circular cracks on massive components).

[nomoresonys]

Examples of bad solder joints: https://www.google.com/search?client...h=541&dpr=1.09

[Crux85]

The solder joints on the main transformer was the problem. Not sure if it was just a faulty solder or if something developed over time, but the joints were still solid. I just cleaned up the problem joint with a quick filing and I've had no issues the last few days.