Bright spots on Samsung TV

[jar]

Hi

We have a Samsung TV (UE50MU6120) which developed the seemingly common fault of several bright spots over the screen. All the information online suggested it was the LED lens covers/reflectors which had come loose.

I have just got round to dismantling the TV today to discover that all of the reflectors are still in place. Pretty annoying as I'd assumed the fix would be just to stick them back in place.

Does anyone have any ideas on what else it might be ?

Thanks

 

[jurassic sparkk]

I do not think it is the "lenses came loose" in all cases but rather an LED burning out and the remaining ones on the circuit get brighter. As more LEDs burn out then the others get brighter until you hit the tipping point where the entire backlight fails.

LEDs need inspecting.

 

[jar]

Hi
Thanks for replying.
If some of the LEDs have burnt out would there not then be dark spots on the screen or do they not necessarily go out completely even if they are failing ? I'm not really noticing any dark or darker spots on the screen.
I know you can buy the strips of LEDs but the plan isn't to keep this TV as we already have a replacement. Not really cost effective to get it repaired if it's nearly £100 for new LEDs.
Would anyone know the correct part number for a full set of LEDs for this model (UE50MU6120) so I can check for prices ?
Thanks

 

[securespark]

My 2014 Samsung TV is doing the same. Every week we switch on, there's more spots showing. It started a few months ago and now there's 13 spots. All are white apart from one that is blue. When it starts annoying us too much, we'll get a new one.

 

[jurassic sparkk]

My 2014 Samsung TV is doing the same. Every week we switch on, there's more spots showing.

Have you checked the backlight LED's?

 

[jurassic sparkk]

Hi
Thanks for replying.
If some of the LEDs have burnt out would there not then be dark spots on the screen or do they not necessarily go out completely even if they are failing ?

Sometimes it cannot be noticed, especially from a "quite" far away distance. Nothing hurts to disassemble the TV and (visually) check if any of the lights are failing.

 

[jurassic sparkk]

My 2014 Samsung TV is doing the same. Every week we switch on, there's more spots showing. It started a few months ago and now there's 13 spots. All are white apart from one that is blue. When it starts annoying us too much, we'll get a new one.

Does turning down the brightness help?

 

[securespark]

Have you checked the backlight LED's?

No. I'm a bit of a clumsy forker these days and knowing my luck if I attempt that, we won't have a TV any more!

Does turning down the brightness help?

No.

 

[securespark]

If turning the brightness down did help would that help you diagnose the issue?

 

[jar]

Hi
It was a challenge to get the TV apart without damaging anything, especially the actual panel. I also couldn't leave it disassembled for long as it was on the dining room table ! So once I found all the diffusers were still in place I just put it back together as I wasn't sure how to proceed.
If I do attempt it again, what would need to be there to get the LEDs to power on without the panel ? Will they just power on so long as there's power to the TV ?
Thanks

 

[jurassic sparkk]

Yes, that would most likely be the "backlight bleeding" instead of a failed backlight strip.

Backlight bleed through from being an edge-lit TV. A possible cause may be the tightness of the frame to the screen. Loosening the frame (the screen directly behind the screen, along the periphery) may help to resolve the issue.

I bought a crappy edge-lot LCD some time ago that had similar problems to yours and reducing the brightness did help quit a bit. Reducing the tightness did help quite a bit. It didn’t 100% eliminate the problem, but it did improve it by a good 50-75%, which certainly isn’t nothing.
@securespark

 

[jurassic sparkk]

Will they just power on so long as there's power to the TV ?

Most TV's supply voltage to the LEDs when woken up. There usually is a circuit that starts and monitors the LEDs at first startup. (That is why you see a white screen when first turning the display on.)

TV display must be turned on when testing. Just a visual inspection will do.

It's best to get it looked by a TV repair shop. They usually know what they're doing.

 

[bernardgreen]

Spots suggest individual pixels have failed. Not much can be done to repair that sort of failure.

 

[jar]

Hi
Agree that we'd normally just pay someone to fix it for us. But, as I said, we've already got a replacement TV so not cost effective to do this as we're probably not going to be keeping it. Sticking the diffusers back on wouldn't have cost anything apart from a bit of my time. We could then have given it away or even got some cash for it as a working TV. I'll have a think about whether to go through dismantling again. Worry is I wouldn't be as lucky next time and then have a REALLY broken TV !!
Thanks

 

[foxhole]

Had same problem with my Samsung, light areas and also purple hue to other areas .
Repair not viable according to my cousin ( Samsung authorised repairer).