Samsung UN65NU6900FXZA Vertical Gray/Dim Area

[80r15]

My gut instinct is that the panel needs to be replaced, but looking for outside opinion on any other possible cause, hopefully without the excessive cost to fix/replace. I'm going to take the time over the weekend to take a look at T-con and check voltages, but again, given the pattern on the screen, odds are slim, if none, that is any potential contributor to the issue observed.

Thoughts? Much obliged, and Happy Holidays!

[lotas]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

If you are talking about a dark spot on the screen, then it looks more like LEDs (fail), there is no separate T-con on this chassis, it is built into the motherboard.

[Diah]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

its remark of the panel will be shorted soon.. don't waste money,, NU TU MU all rubbish panel.

[lotas]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

Well, the MU series is still tolerable with a panel and backlight, but the NU, TU, RU series - yes, one marriage.

[Diah]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

lotas at the end all with U end are Sami fucking cheat.

[80r15]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

If you are talking about a dark spot on the screen, then it looks more like LEDs (fail), there is no separate T-con on this chassis, it is built into the motherboard.

No, it's that entire gray area. It would be nice if it were the LED's, but not the case...

[nicholas1110]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

This does look like failed leds. Specifically maybe only 1 or 2 leds out. You can see on the bottom one specific spot were it is slightly darker which is the led that is out. You can confirm by removing the screen and turning the leds on you will likely see a few not lit. It’s very common on this series of TVs. Leds are inexpensive for this model and worth replacing as long as the diffuser here has not melted or cracked.

[Storyteller12]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

lotas at the end all with U end are Sami fucking cheat.

I agree. I'm curious what tv you have and what brand/ models you recommend?

[Diah]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

I agree. I’m curious what tv you have and what brand/ models you recommend?

now days all brand start with low coast production ( All In ALL ) no recommendation.. but before was all brands hold long.. as my Hisense from 2016 & LG 3D LA series from 2013, both until now never opened the back cover...

[80r15]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

This does look like failed leds.

Yeah, I now think that's the case. I put up the post to get some quick insight before I had a chance to completely dissect the design of the device. As it turns out, this only has the bottom/top *two* LED strips (finally took the time to look at the internal specs this evening), so that means the issue at hand is completely feasible. Had I known there were only two, my initial impression would have been much different, but it's been roughly eight years since I did a repair on one of our tv's, so of the cuff I was still thinking of the old school way.

You're right, LED's are cheap, so ordering some tomorrow, worth the risk since odds are in favor (drastically).

Thanks again!

[nomoresonys]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

.

[Ihandyrepair]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

Samsung uses bottom edge for the led back lights, specially the NU mu models. The worst parts, if led failed or burnt, diffuser might be melted or cracked.
I just finished replacing on 50NU Samsung burnt one side led backlight. Melted diffuser. Had to cut the melted area and turn the white back paper 180 as there some brown burnt area.
At first I cut only the melted area. Put everything back, not good. Tv would have white spots areas at the bottom where the light passes through the cut area. Forgot to take pic.
Tried again by cutting the entire lane bottom and works, image looks even. No brown spot.
Not much I could do with the crack, slight white spot area

[Diah]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

Tried again by cutting the entire lane bottom and works, image looks even. No brown spot.

interesting ,, how did you succeed cutting the hard defuser plate with out break it !!?

[Ihandyrepair]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

rotary tools, make sure is sharp and cut small amount at the time. Need to find the right speed and force.
Too fast too much, you can melted the diffuser instead of cutting.

Here are the only downside
After cutting the bottom, removing the melted brown area, the diffuser is a little shorter at top.
There is a small gap, so you can see a little whiter on top, light leaks out
So next time, I know, I will put white tape so light can't leak out.
Didn't want to remove the panel again, already did so many times,
Worry I might break it.

Pictures with colors is not that bad
You can still see a little of the crack when the image is white.
But this is so much better image at the bottom.
Before I remove the bottom section, the right side would show bunch of white spots.

[alfatv]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

Not all NU's are that bad, sometimes backlight replacement is enough.
There is separate thread about NU meltdown, better post your findings over there:
https://www.badcaps.net/forum/showthread.php?t=96567

[80r15]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

Thanks guys, it was indeed the LED strip, finally had time to do the replacement last night and the picture is back to normal. After looking at photos, Samsung service said that they wanted to replace the panel, for *only* $1055...

[80r15]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

OMG... and less than 24 hours since swapping the new LED strips and the new strips have failed.

[lotas]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

Well, apparently they installed not high-quality ones, a Chinese fake.
When installing a new backlight, it is necessary to glue it on hot glue or thermal adhesive tape (heat-conducting heat-resistant double-sided tape) and limit, reduce the backlight current in the power supply.
https://www.youtube.com/watch?v=YEbxGmBBYjE

[80r15]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

Well, apparently they installed not high-quality ones, a Chinese fake.
When installing a new backlight, it is necessary to glue it on hot glue or thermal adhesive tape (heat-conducting heat-resistant double-sided tape) and limit, reduce the backlight current in the power supply.

I used these from ShopJimmy. The strips are installed with double-sided tape, can't verify that it is indeed thermal, but it came preinstalled on the strips. What is the reason for needing to reduce backlight current in the power supply?

What is odd is that we turned the tv off when we went to dinner last night, and when we returned we turned the tv back on and the section of LED's that were no longer working *were* working, but only for roughly ten minutes and the rest are uneven in output. Thoughts other than bad strips?

[nomoresonys]

Re: Samsung UN65NU6900FXZA Vertical Gray/Dim Area

well your Right Diah, NONE of them are any good.