Another sony led back lighting problem.

[freakaftr8]

Re: Another sony led back lighting problem.

only trouble is,an lcd panel has many diffuser sheets in them,trying to define a faulty led can be hard,with ccfl,you have more of a chance,as if one fails it tends to give a uniform shadow,but the feed back circuit will prob only give you around 2 secs to see before it shuts the inverter down.

THis is very true. Best way is usually the hardest by removing the panel..then doing g my power up trick..

[tibimakai]

Re: Another sony led back lighting problem.

Which one is the balancer?
To me, it looks like one of the LED driver ICs must be bad. I had pretty much the same thing, but half of them didn't light up. I had two ICs out. Mine it was an 46NX720 model.

[multimeter]

Re: Another sony led back lighting problem.

only trouble is,an lcd panel has many diffuser sheets in them,trying to define a faulty led can be hard,with ccfl,you have more of a chance,as if one fails it tends to give a uniform shadow,but the feed back circuit will prob only give you around 2 secs to see before it shuts the inverter down.

[freakaftr8]

Re: Another sony led back lighting problem.

Never mind. I found a hole burned in one of the balancer Ic's. either going to try to rebuild the balancer board or replace it not sure yet it appears that this board is hard to find.

on another note I did learn something new that might come valuable to other members. If you disconnect the LVDS cable from the tcon board then as you are plugging in the TV hold the power button at the same time you will get a momentary white screen and it will light up all LEDs for approximately 1.5 seconds and you can do this again and again and you will be able to see if you have any bad LED's behind the screen. I came across this on accident but it appears that it is a useful tool in trying to find a bad led.

[freakaftr8]

Kdl 55hx729 picked it up tonight with a 5 blink code. Repaired the bad ribbon LVDS cable and found that the LED's on a quarter the bottom go out after 2 seconds of being on. Of course this throw the for blink balancer issue. I'm thinking it is a certain led problem due to the fact that they do work upon first startup. after testing the balancer board I am pretty certain that led is overheating and shutting down immediately incense the LED's are wired in series one goes out the rest go out. I think I'm just going to pull the panel in check the LED strip one by one. Has anybody had any success rate at this problem.?

I know there has been a few other members on the forum having the same issues with their LED Sony backlit TV. Has anyone successfully repaired this yet?

http://i845.photobucket.com/albums/a...ps42cfe091.jpg

http://i845.photobucket.com/albums/a...ps4b65285e.jpg