1

I have a Samsung TV 50 inch U7000 and the brightness is all wonky and I don’t know if it’s a backlight, power supply or a main board issue. It’s no longer in warranty and planning on fixing it myself, but I don’t know what the issue is.

The brightness control is set halfway, if you increase it, the screen flickers and continue getting darker, it acts like there’s no brightness control

3 Spice ups
2

Main board issue, it is more cost effective to replace the whole tv nowadays.

3

They are not hard to work on, just large and in charge. AFA the mainboard goes, I see what I think is the right one (need to verify part number) on ebay for about $40 free shipping and 30 day warranty, and if you make sure that the seller offers a warranty, then you can buy the board, install it and if it fixes it great, if not send it back for credit. Also a good resource Shopjimmy a bit higher but the utmost in warranty and support.

These use LED backlight strips, so if the symptoms are that the whole screen changes brightness equally, it is likely as mentioned, a logic board issue.

But at a risk of $40, I would give it a shot.