Samsung UN46EH5000, No Backlight

[ame123]

Re: Samsung UN46EH5000, No Backlight

Alright it looks like they are soldered together.....

https://www.shopjimmy.com/catalogsea.../?q=un46eh5000

https://www.shopjimmy.com/samsungltj...face-board.htm

So these LED strips for sale with the interface panel are for the same model TV, but for a different Panel then mine. The mounting looks the same, the LED count and spacing looks the same, and the LED interface board has the same part number and connector is also the same.

My questions is do you think this might work?

[budm]

Re: Samsung UN46EH5000, No Backlight

It uses interlocking connectors and hard to release.

[budm]

Re: Samsung UN46EH5000, No Backlight

Alright it looks like they are soldered together.....

https://www.shopjimmy.com/catalogsea.../?q=un46eh5000

https://www.shopjimmy.com/samsungltj...face-board.htm

So these LED strips for sale with the interface panel are for the same model TV, but for a different Panel then mine. The mounting looks the same, the LED count and spacing looks the same, and the LED interface board has the same part number and connector is also the same.

My questions is do you think this might work?

I would contact SJ to find out for sure.

[budm]

Re: Samsung UN46EH5000, No Backlight

So I type in 'BN96-21487A' and this comes up:
https://www.shopjimmy.com/catalogsea...?q=BN96-21487A
https://www.shopjimmy.com/samsungltj...face-board.htm

https://assets.shopjimmy.com/media/c...strips-top.jpg

[ame123]

Re: Samsung UN46EH5000, No Backlight

K, I figured out on how to take em off. I Spoke to SJ, they can neither confirm nor deny if it will work or not. I guess I'll just have to give it a shot. The only difference I can see in the LED strips is that the one they have is made by Samsung and the one in my TV by Lumens.

[budm]

Re: Samsung UN46EH5000, No Backlight

BTW, any of the LED looks blackened?

[ame123]

Re: Samsung UN46EH5000, No Backlight

No, not a single one looks bad, I have to buy some batteries. Is there any other way of testing them that you could think of. The easier the better.

[ame123]

Re: Samsung UN46EH5000, No Backlight

Just test all the LEDs, 1 is bad. I'll probably buy the LEDS for the other panel for the same TV. see how it goes.

[Patch2]

Re: Samsung UN46EH5000, No Backlight

I've got the same model TV, with the same problem. I tested the 450V cap, and got 392VDC plugged in, 12VDC unplugged. The D1+ pin on CNL802 tested at 225VDC after 3 seconds of plugging in. Am I looking at the same failure in the LED strips?

[Patch2]

Re: Samsung UN46EH5000, No Backlight

Here's some photos. BTW, my model is UN46EH5000F-XZA, version UD03.

[SLK001]

Re: Samsung UN46EH5000, No Backlight

Am I looking at the same failure in the LED strips?

Can you see a display with a flashlight? If so, then you probably have a bad LED also.

[budm]

Re: Samsung UN46EH5000, No Backlight

I've got the same model TV, with the same problem. I tested the 450V cap, and got 392VDC plugged in, 12VDC unplugged. The D1+ pin on CNL802 tested at 225VDC after 3 seconds of plugging in. Am I looking at the same failure in the LED strips?

Yes, you have open circuit in the LED strips.

[Patch2]

Re: Samsung UN46EH5000, No Backlight

Can you see a display with a flashlight? If so, then you probably have a bad LED also.

Yes.

[Patch2]

Re: Samsung UN46EH5000, No Backlight

So, if the diagnosis is a problem with the LED strips, can anyone comment on whether or not it is worth the time and money to replace them? Is this an enduring repair, or really only temporary in most cases? I saw at least one post where the problem came back after being fixed and working for a while. Saw another post where the poster felt that once the LED strips go bad, the TV is ready for the recycle bin.

[SLK001]

Re: Samsung UN46EH5000, No Backlight

So, if the diagnosis is a problem with the LED strips, can anyone comment on whether or not it is worth the time and money to replace them? Is this an enduring repair, or really only temporary in most cases? I saw at least one post where the problem came back after being fixed and working for a while. Saw another post where the poster felt that once the LED strips go bad, the TV is ready for the recycle bin.

What I am seeing in a lot of strips, is that the hi-temp solder didn't properly flow - meaning that it didn't reach its liquidus state. The result is a poor (cold) solder joint. A lot of joints that I see are crystalline. I always scrape the old solder on these down to the copper, then replace with 63/37. I have to scrape, because I don't want to put the heat required to reflow the hi-temp solder and wick it off.

The newer strips are actually a pretty good design, with enough board area to properly dissipate the heat. The problem is that with a cold solder joint, the heat can't get to the heatsink area fast enough - thus it stays in the LED and overheats it.

An LED with a good solder joint should last a long time.

[Patch2]

Re: Samsung UN46EH5000, No Backlight

So, how do I test the LEDs? I tried putting two AAA in series, and testing at the two holes on either side of each LED, but that didn't work. I assume those small holes are there for just that purpose, correct?

[SLK001]

Re: Samsung UN46EH5000, No Backlight

Find yourself something metallic that will slide under the lens and contact the side of the LED. Straight pins will sometimes work, but sometimes I have to use pieces of 28 gauge wirewrap wire. Stiffer items are better for a beginner. Two batteries usually will work - most LEDs are only of the 3V variety. Once you have built your LED tester, determine which of the four ways your LEDs are attached, then start testing, one at a time.

Sometimes you can look directly down at the LED through the lens and see discoloration from a burned out LED. If you can find one of these, then slip a thin screwdriver under the lens and pop if off. You can then figure which way to test the rest.

What is your skill level and what tools do you have access to?

[Patch2]

Re: Samsung UN46EH5000, No Backlight

What is your skill level and what tools do you have access to?

Basically, a jack of all trades, master of none. I've done a little bit of everything, EXCEPT electronics, although I have done some automotive wiring. So, this is my first endeavor in this area. I have a multi-meter, a couple of soldering irons, and a bunch of automotive wiring fittings.

[Patch2]

Re: Samsung UN46EH5000, No Backlight

I was able to figure out where to test the LEDs individually, using a home-made 3VDC test cell (2 AAA batteries in series, with straight pins soldered on). The pins slid under the LEDs perfectly.

I found 4 bad LEDs, on 4 separate strips. Problem is, all the discount stores are out of stock (Shop Jimmy included). Looks like they are not making them anymore. Electronica USA sells strips at $20-$24 a piece (as opposed to SJ at $60 for a set of 8). I was going to buy all new strips to lower the risk of having a reoccurrance, but that's $164 + shipping. That's alot to spend considering the questions still remain: How did the 4 LEDs go bad in the first place? What would keep the same thing from happening again?

I'm going to have to think on it for a while. It may be time to let this one go.

But it's been a great learning experience. I now know a little more about how a TV works.

Thanks for all your help!

[ozzy214]

Re: Samsung UN46EH5000, No Backlight

I was able to figure out where to test the LEDs individually, using a home-made 3VDC test cell (2 AAA batteries in series, with straight pins soldered on). The pins slid under the LEDs perfectly.

I found 4 bad LEDs, on 4 separate strips. Problem is, all the discount stores are out of stock (Shop Jimmy included). Looks like they are not making them anymore. Electronica USA sells strips at $20-$24 a piece (as opposed to SJ at $60 for a set of 8). I was going to buy all new strips to lower the risk of having a reoccurrance, but that's $164 + shipping. That's alot to spend considering the questions still remain: How did the 4 LEDs go bad in the first place? What would keep the same thing from happening again?

I'm going to have to think on it for a while. It may be time to let this one go.

But it's been a great learning experience. I now know a little more about how a TV works.

Thanks for all your help!

Whats the part numbers on the led? I have leds from a 32" smashed screen television that may interchangee. I would sell the whole set for like 45 shipped. They have the same tab locking mechanism as these so wondering if they interchange!

It may be worth to save a 500 set for 40 bucks, kinda no brainer. Plus the general consensus is if you turn the backlight down, they last quite a long time.

The part number I have on my strips is
32h-353led-32ea

There is 8 leds per strip and 4 strips.

So perhaps they interchange?

Not trying to make a sale...just trying to help! And I dont sell untested parts or gambles. I actually power everything on and hook to a laptop to make sure it is working. As a cracked screen is not always a good indication parts are good!