LG 47LW5600 Has picture, No backlight, then I made it worse :-)

[Lawdawg79]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

No worries, I ordered some fuses but I went with cheap and longer shipping vs expensive and get it this week. I do wanna get this thing up as soon as I can but its not as if we are without a TV. I looked through some scrap circuit boards I have, but no luck on any of those either.

Last summer I put a 50" LG plasma in my master bedroom as an upgrade to the 42" I had in there since 08'. I didnt think about how much heat a 2006ish model 50" plasma puts off. We have to keep the bedroom door open in the summer if were watching TV in there. We were about to spend 3-400 in the next few months (before the July and August heat) to get a cheap 50ish LCD, and then this fell in my lap. So a blessing in a way I suppose.

Will report back once I get the parts in.

[dskall]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

Where is Caseyville? I live in Bakersfield. It has already hit 105 here.

[Lawdawg79]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

Illinois, Just about 20 minutes across the river from St.Louis... were still running in the midish 80s right now, 57 tonight!! but its HUMID so even 65 doesnt feel all that pleasant.

Last year we had a portable air conditioner in the bedroom to keep it cool in there. But the problem was the central AC having only one central air return. I knew My problem wasnt supply of cold air, it was removal of heat from all the rooms. Did a return air duct project over the winter so its not as bad in the bedroom and the entire house feels alot cooler throughout. But that plasma gotta go, its gonna become the back porch TV or something.

[Lawdawg79]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

I was in Vegas in March for my honeymoon and made sure to stop in at the In and Out burger , it had been years since I had some animal fries and a 2x4

[Lawdawg79]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

Alright fellas, Im back, the fuse has been replaced and we are somewhat back in business, meaning she fired back up but with no lighting behind the screen. So where should I start on this thing?

[Lawdawg79]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

Ok well i guess i will see about getting to the LEDs themselves and test them out. If i just find one or two, can i just bypass them and fire it back up? Or would it not look right?

[attainteddragon]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

don't bypass them. even if it works for a bit, the strings will not draw the same amount of current and you will just end up with others failing.

either replace the failed led's or the whole strips that have failed.

is the ps up and running again?

[Lawdawg79]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)






Yes everything fired back up, i only see diodes on the sides, i dont see any behind the screen.

I dont see a way to test them either.

[Lawdawg79]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

I dont know what photobuckets problem is

[Lawdawg79]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

Ok upon further research these are just lit by left and right led strip/brackets.

They look to go from 60-175ish on ebay.

So is there some way to modify the led driver so it doesnt pump out so much power? Or is it good enough to keep the brightness down.

[Lawdawg79]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

And photobucket wants 400 a year now!!! F that

[dskall]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

Not seeing them they are probably around 6v led's. Apparently they are lit in groups of 10. If you had led tester or variable power supply you could test them. I have never had edge lit tv. I would imagine you can replace them individually. Better you upload from here. Go advanced, manage attachments

[Lawdawg79]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

Thanks for the tip...here ya go....oh and that makes 2 of us, i didnt even know they made em like this lol.

[attainteddragon]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

edge lit led's are not that bad to change out. it is getting the right replacement led's that is a bit trickier to get.

first you need the right voltage led's,
then you need the right footprint,
then you need the right anode/cathode configuration.

with testing, these may be dual 3v led's, so you need to make sure both halves light up.
you can just test each side with your mm in diode mode. orientation can change half way through the strip.

hot air is the easiest way to change them in my view.

[Lawdawg79]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

Hot air? Is that to say use a heat gun to get the strip off? Because they look like they are glued to the aluminum frame.

[attainteddragon]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

i use my rework station, but it is meant to be possible with a heat gun. norcal did it in one of his vids.

first step is knowing how many led's need to be replaced.

[Lawdawg79]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

I will have to look again, but it looks like one continuous strip for each side.

What about warming them in the oven??

[attainteddragon]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

you can't oven them as they would all slide around even if you were incredibly careful.
there are led hot plates you can get that heat in a more localized manner.

the strip that is not lighting needs to be tested for individual led function unless you are going to change out that strip.

[Lawdawg79]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

Well, i dont have a workstation. But im pretty crafty so im not scared to try things. Just not sure which direction to go, id like to fix it the cheapest way, but if im better off just trying to find a used set on ebay then thats what i will do.

But i dont want to spend time and money on something that is just going to go out again due to a design flaw.

[dskall]

Re: LG 47LW5600 Has picture, No backlight, then I made it worse :-)

Keep backlights as low as possible