Count of Leds burnt in backlight POLL !?

[web5]

How many Leds you discovered Burnt when you openned TV ?

I have TV with backlight stopped working, and
before i start to tear down it, i would like to
narrow down to the number of possible burnt Leds.
( Tested power supply - power does not go to led strips)

[chrismurphy]

Re: Count of Leds burnt in backlight POLL !?

I think this is rather useless as every tv and tv's same model differs
It wont help at all , what would be better is the working voltage of the strings for various models would be helpful , better still the running voltage using LED tester would help narrow the fault to LED panel or power supply driver

[web5]

Re: Count of Leds burnt in backlight POLL !?

I think this is rather useless as every tv and tv's same model differs
It wont help at all , what would be better is the working voltage of the strings for various models would be helpful , better still the running voltage using LED tester would help narrow the fault to LED panel or power supply driver

Before i tear down tv for repair i would like to order some quantity of led
replacements, and how many is more likely be enough.
Tested yesterday, my 50" TV led supply puts 124.5 VDC.

[ReeceyBurger123]

Re: Count of Leds burnt in backlight POLL !?

Ive had 18 out before in Lg 50"

[web5]

Re: Count of Leds burnt in backlight POLL !?

Ive had 18 out before in Lg 50"

Wow, didn't expected that number !
On Tube i see from 2 to 4 leds blown.

[freakaftr8]

Re: Count of Leds burnt in backlight POLL !?

Ive had 18 out before in Lg 50"

Good god man that's a tv that doesn't want to be resurrected fro. The dead!!

[dskall]

Re: Count of Leds burnt in backlight POLL !?

Before i tear down tv for repair i would like to order some quantity of led
replacements, and how many is more likely be enough.
Tested yesterday, my 50" TV led supply puts 124.5 VDC.

15 should be enough

[web5]

Re: Count of Leds burnt in backlight POLL !?

15 should be enough

1/5 of all leds in my tv, i think you are right.

[ReeceyBurger123]

Re: Count of Leds burnt in backlight POLL !?

Good god man that's a tv that doesn't want to be resurrected fro. The dead!!

Tbh I dont know what happened as 6 were open and 12 shorted LG LN series always seem to fail badly

[budm]

Re: Count of Leds burnt in backlight POLL !?

12 on SAMSUNG, 9 open, 3 shorted.
I would stock 50 of them (I order 100 at a time. How much is the price difference between 15 and 25 or 50?

[goontron]

Re: Count of Leds burnt in backlight POLL !?

The only LED TV i've worked on -- Vizio, 50" IIRC. struck by lightning. All LEDs open.

[whiz62]

Re: Count of Leds burnt in backlight POLL !?

Vizio 47", 4 LEDS open out of 54.

[augiedoggy]

Re: Count of Leds burnt in backlight POLL !?

I have found that about 30-40% of the tvs I just replace the burnt leds instead of the strips end up having another led failure shortly after. I think one of the reasons being is if an led shorts closed the voltage increases to all the other leds and stresses them. some tvs only have one shorted open led and thats all it sometimes takes to make the whole tv go dark and on other sets Ive had to replace as much as 5 bad leds. By far the most unreliable LEDS are the ones LG uses in their economy sets as well as many of the vizios they make. (I have an LG 47" set sitting here now I have to repair AGAIN after replacing the bad leds and having another fail 2 weeks later.)

[dskall]

Re: Count of Leds burnt in backlight POLL !?

I am modifying the current supplies to the leds on vizio and LG. They run there current at 400ma+ on leds only rated for about 350ma. I want to set them below 350ma. Funny thing is I reduced max. current over 100ma with little noticeable change in brightness. Makes you wonder if it's calculated to kill the tv after warrantee the same as the failing bad caps did.

[augiedoggy]

Re: Count of Leds burnt in backlight POLL !?

I am modifying the current supplies to the leds on vizio and LG. They run there current at 400ma+ on leds only rated for about 350ma. I want to set them below 350ma. Funny thing is I reduced max. current over 100ma with little noticeable change in brightness. Makes you wonder if it's calculated to kill the tv after warrantee the same as the failing bad caps did.

Curious, Will you share how are you modifying them?

[dskall]

Re: Count of Leds burnt in backlight POLL !?

Just learning this stuff. Need to modify led controller current sense resistors.
https://www.badcaps.net/forum/showthread.php?t=61722