I have an old Samsung UE55C8000XPXZT that after a storm started to shutdown itself after a few minutes of use.
While I'm using it for the few minutes it stays on, it behave normally, after that the display flashes a couple times and it turns off (but the TV is still on even tho black screen and no audio). To revive it I have to unplug the power and leave it rest for a while.
Maybe someone can help me identify the issue. I'm quite affectionate to this TV and I'm all in for saving money and the environment without going for a new one.
We had a Samsung TV that did something similar. Fortunately, I had bought extended 5-year warranty for it with a third party. Called them up. They sent a repair person who opened the TV. It's amazingly compact. All the electronics were in a couple of low profile circuit boards. He pulled the connectors, popped off the boards and snapped new ones in. It was surprisingly easy. You can take the whole thing apart with a screwdriver.
The whole thing is integrated. There's no way to fix an individual feature. It may be the power supply is not functioning right, but you have to replace the whole motherboard with the power circuitry. You can find spare parts on ebay or through authorized repair people.
In our case, they swapped all the PCBs twice and it didn't fix the problem. The insurance offered to swap the TV with a newer one but the specs were much worse. They ended up refunding the purchase price. Got an LG. Much better color quality IMO and hasn't failed yet.
This is not true. However OP, I'm pretty sure you don't have the knowledge to fix this kind of damage. I suggest to look for an electronics technician that can help you out. Depending on your budget, it might be cheaper to buy a new one than to pay to get it fixed but if it has sentimental value or it's just a dumb TV (nowadays that is a feature IMHO)...
I can't tell from the video but I think you might have a dead capacitor somewhere. I'd suspect on the psu-board. Look for one(s) that bulge at the top.
Just look online on how to replace them if this is the case. Fairly easy and cheap.