I have horizontal lines on part of my TV screen.

One thing you might want to try is give the TV a few wacks on the back. Just lightly hit the Tv a few times on the back all around, and see if that fixes your issue. if it happens to, or when doing it you see the lines go away but come back right after you hit it, it could be a loose connection, If it doesnt, report back and we will explore other options.

But sometimes hitting it actually works!

I was told many things it could be the panel or t con boards so I did some more research and it always led to same thing so a local guy who repairs tvs told me before paying for parts or anything like that take the back off and disconnect all the connections wait a few minutes put them back on and my tv works again.. my problem was when I would turn my tv on after a few minutes the screen would jump around with horizontal lines then go away and come back after a few more minutes, what can cause that is loose cables inside the flatscreen itself or even dust that builds up can interfere with the picture I highly recommend you trying this before paying to have it repaired with new parts or throwing it out as my tv is bran new 60 inch flatscreen RCA it may seem like alot to do and technical but I'm not a technology person it just takes 15 minutes out of your time to take screws out disconnect cables put them back on and put the back cover back on and from doing that my tv is back to normal

My Tv is a Chinese brand and the line appeared after 3 months. The problem is I move the Tv everyday from room to room so something came loose. I connected the ribbon connector firmly and the lines disappeared but once I reassembled they appeared again. I turned the TV upside down and the lines disappeared. This tells me that the ribbon itself is no longer secured. I tried using electrical tape it didn’t work only made it worse.

I’ve fixed my tv. The problem was the ribbon cable which goes to the panel was getting short circuit. Had to replace the two cables from the panel. This is not a DYI project. I had a technician who did the repair. Hope it’ll help.

Hello there! I had the same issue with my Sony Bravia Tv and I found a solution on my tv manual. Check your tv coax cable and remove it. If that resolved the issue meaning you need to change coax. If your coax is rated 300 ohm, used 75 ohm instead. So far, i dont get the line anymore!

I had fine horizontal lines and grainy screen with shadowing on my 55” LG LED TV. It was about 10 years old. Took t-con board and data board out of TV and preheated my oven to 210 degrees Celsius, baked them for 10 minutes exactly on a pizza tray. Put TV back together. Working like new again. Vic H.

Ours is a Sony Bravia that is now over 10 years old. Several months ago we started noticing lines, especially on the left (our left) side of the screen. They’d go away after the tv warmed up. Then we started noticing it was darker on that side of the screen, but again, after the tv warmed up the screen would be normal. Then about two months ago it started getting worse and didn’t ever get completely better, even after the tv warmed up. So I watched some youtube videos that all talked about the ribbon cables becoming loose over time and to apply pressure along the top and see if that made it better, and if so, it was a loose cable and if you put electrical tape or something that would help keep the pressure, it would fix the problem. Hubby pressed along the top and sure enough, when he pressed in one spot on the left side suddenly the picture cleared up. Stayed good for about a week, then problems again, pressed again, fixed again. A week or so later, same problem, but this time when he pressed on it nothing got better.

So I decided to take the cover off and look at it better. As I was pressing on the tops of the ribbon cables that run down from the top of the frame, for a minute it got better but then suddenly there was a wide white vertical line, with a thin green one down the center of it, running down the front of the screen, and it was perfectly aligned with one of the cables. So now I still have the dark side of the screen, and some ghosting, and some lines, but now this bright white streak/line right down the front. Another weird thing is that if the whole screen is bright (like watching a show set in a snowy place) then the darkness even on the left side is basically gone, but if the scene is dark at all, that side is almost black. I don’t know if it means that particular ribbon cable is bad, or if something is loose, if things need to be replaced or what. It’s very frustrating as it’s been a great tv. Hubby wants to just buy a new one, but even if he does I would still like to try and figure out this one as it could then go in another room.

I have a Samsung. The higher resolution output of the TV causes the lines, going to lower HD still gives an outstanding picture quality and got rid of the lines.

try that it's working for me :

https://www.youtube.com/watch?v=wPPlqHu_...

Same issue but side note to solve input issue from streaming and casting devices

If you are using a stick to stream with of some sort I just spent some time trying to fix my lines and I went into the stick settings and it said "always play as HDR"

I turned that off and now streams are playing like they are meant to as some cartoons are made in 720 or 1080 and by forcing 4K it was trying to upscale something that wasn't there resulting in flaws in the picture and lines.

It will still play 4k streams if they were shot or encoded in 4k or made in 4K depends how you set it.

I've just turned mine off or you could also set it to 1080 at 60 frames per second or auto and I've gotten rid of the issue and everything looks incredible again.

Cartoons are poppy and beautiful without any artifacts or lines or noise and live action is much better too as it's playing whatever format it was exported to for streaming if that makes sense.

I have a Hisense 4K 75 inch screen. It's now flawless I must have changed the setting in the Roku, Fire stick, Chromecast (whatever device you use) by accident thinking it would make the picture better. I was wrong you need the video files to play in their native formats just like Nolan intended.

Hope this helps someone