LED Failure

[Andrew F. Ali]

My question: Do LEDs always fail open or can the fail short circuited in a backlight arrangement??

[ReeceyBurger123]

Re: LED Failure

Fail open will cause the whole lot not to light.

If a few are short the backlights will work, if more go though protection will kick in and shutdown the backlight.

[Andrew F. Ali]

Re: LED Failure

Thanks Reecy.....

[ReeceyBurger123]

Re: LED Failure

No worries brother

[Andrew F. Ali]

Re: LED Failure

Well I guess if they fail short then we would still get backlight, which may not be a bad thing. However, fail open then no backlight as they are connected in series. Thanks.

[ReeceyBurger123]

Re: LED Failure

Spot on, short just dumps the excess load on the others where as open they cant be loaded so the driver shuts down but it lots short the driver will eventually detect it.

[Andrew F. Ali]

Re: LED Failure

I looked at your very informative video on backlight stacking. Very nice indeed!!..I have a LED failure to investigate and not too sure on how to handle the LCD glass. What is the best way to hold this for removal and return??...Thanks

[ReeceyBurger123]

Re: LED Failure

Cheers for the feedback

Also remove the frame then flip the Tv over whilst holding the frame to keep the glass in place (only if its a Vestel and does not have a metal chassis for the Lcd screen) then unmount the tab bond boards as shown in the video and use something like electric tape to secure them in place. Then I normally get my finger nail under that glass and pry it up then grab the sides and carefully set it down somewhere safe.

[Andrew F. Ali]

Re: LED Failure

Excellent.....

[ReeceyBurger123]

Re: LED Failure

No worries keep us updated.

[Brian_STI]

Re: LED Failure

BTW, a lot of LEDs can short and still have the unit working. I just disassembled a Samsung that had 19...19 bad LEDs, it had 19 good LEDs. When one finally failed open was when the TV finally failed and was brought into the shop. Worst case of bad LEDs I've seen, no rhyme or reason, good and bad were scattered through the strips. I'm not sure of the make of these particular LEDs but they look the same as the full array LGs, which also fail all the time.

[Andrew F. Ali]

Re: LED Failure

I need to get a LED Backlight Tester. The GJ2C...Its about 50US..Thanks