Screen doesn't power on, flickers on and off, is it possible to repair

Question

Samsung Television

2610 Perguntas Visualizar todos

John Dough @johndough12

Rep: 35

2

Postado: 1 de out de 2021

Opções

Screen doesn't power on, flickers on and off, is it possible to repair

Hello!

The TV in question is actually the un55ks800df model, however ifixit wouldn’t let me select that so I figured this one is close enough. It is not curved and it is a UHD TV from 2017 I believe. Here is what happened:

I was watching it as usual a while back (I’ve been very busy and haven’t had time to fix this for a while) and for some reason all of a sudden the bottom of the screen turned green and then the rest of the screen and then the screen slowly faded out.

Ever since then, whenever you try to power it back on the screen will flicker on, flicker a little bit and then go back off, and then continually repeat the cycle. The Samsung logo in the bottom middle keeps flashing on and off with the screen as well. It won’t stop doing this and pushing the power button doesn’t seem to turn it off, I’ve had to unplug it to stop this cycling.

Any ideas as to what this could be and is it something that I, a moderately adept handy kinda guy who can solder and all that, can fix?

Appreciate all the help!

Hey so I’ve not opened the back of it up yet so I can’t say what is on the boards. I do have a video of what it is doing if that will help and I will get back to you once I open the back up.

Video: https://imgur.com/a/xSxATpS

Also I did a bit of googling with the model number and according to this ( https://www.tvpartshome.com/product/sams... ), the power supply/led board is BN44-00878A, though that site also says that the board number(s) is/are: L55E7_KSM , PSLF191E08A .

Let me know if that’s not enough info and I’ll crack it open and get a pic of the guts for ya. Thanks for taking the time to help out!

Respondido! Ver a resposta Também tenho esse problema

Esta é uma boa pergunta?

Sim Não

Pontuação 2

Adicionar um comentário

1 resposta

Solução escolhida

oldturkey03 @oldturkey03

Rep: 782,4 mil

1,1 mil

893

2,3 mil

Postado: 2 de out de 2021

Opções

@johndough12 that sounds like a driver board issue. Most likely the voltages from the T-con board to the LED driver board. Post some good pictures of your boards (very good pictures) or tell us the exact model number for your boards as well as the LCD panel. there should be a label directly on the metal cover of the panel. You will need to measure some voltages and its going to be very “experimental” since LED Driver boards are not well documented.

@johndough12 Thanks for the posting the video. Looks like it is trying to turn your backlight on. That looks like an issue with either the power board or the main board ( not the LCD driver board for now at least).. You would have to try something else, like when its on disconnect the main board from the power board. That should actually turn the backlight on. Let us know what you find. So yes, remove the back cover and lets see what we find.

Esta resposta foi útil?

Sim Não

Pontuação 3

10 comentários:

@oldturkey03 Ok so I popped the back off and took a bunch of pics of the inside. Which board needs to be unplugged where?

Here are the pics: https://imgur.com/a/lr0OSR4

5 de out de 2021 por John Dough

Try to disconnect the green board from the brown board while the TV does the flickering. See what it does.

5 de out de 2021 por oldturkey03

@oldturkey03 Ok, just as you said, unplugging that ribbon cable made the flickering stop

5 de out de 2021 por John Dough

@johndough12 but still no backlight? It just stopped flickering?

5 de out de 2021 por oldturkey03

@oldturkey03 No the light stays on (assuming that's the backlight?) unless there is more than one light, the backlight is staying on after unplugging

6 de out de 2021 por John Dough

Exibir mais 5 comentários

Adicionar um comentário

@oldturkey03 Ok so I popped the back off and took a bunch of pics of the inside. Which board needs to be unplugged where?

Here are the pics: https://imgur.com/a/lr0OSR4 — John Dough
Try to disconnect the green board from the brown board while the TV does the flickering. See what it does. — oldturkey03
@oldturkey03 Ok, just as you said, unplugging that ribbon cable made the flickering stop — John Dough
@johndough12 but still no backlight? It just stopped flickering? — oldturkey03
@oldturkey03 No the light stays on (assuming that's the backlight?) unless there is more than one light, the backlight is staying on after unplugging — John Dough

Samsung Television

Screen doesn't power on, flickers on and off, is it possible to repair

Update (10/01/2021)

1 resposta

Update (10/04/2021)

Adicionar a sua resposta