Repairing Modern HD-TV flatscreens

[BlackListedB]

It's a challenge I always avoided, that tracing back to CRT tube based sets, main thing was dangerous high voltages that were enough to cause you serious harm, if not possibly injure you some way, some how. But I've been shocked a few times and burned on other projects just the same! 

 

Now, I actually hope not to have to do repairs, but I encountered yet another LCD someone was tossing out with their trash, and I decided I'd at least try and get it home. Well....

 

I did manage the no mean trick, it took about an hour to move the set about 7 or 8 blocks to my apartment, it was between my sister's home and my new one. Not too far, but I have no car, no truck, no trailer, I walked the set! It was a painful affair! 

 

Anyway, it did spring to life initially but then failed to respond moments later. I was able to get a playback signal in non-anamorphic mode, and navigate onscreen menus. For a bit it went to black and caused speaker distorted tones. The screen was in great shape. Of other found smaller screens, several actually worked fine, they were LCD intended for computers. VGA and DVI inputs only. This is the second full on HD set I found that shows signs of life.

 

A further defective unit I disassembled and re-trashed, saving working speakers and electronic sub-sections. In looking at what's available for my replacement parts, I found this site I'd like to pass along...

 

http://electronicshelponline.blogspot.com/2012/05/how-to-detect-t-con-board-faults-with.html

 

Tells you more specifically what a technical term relates to in diagnosis. In my repair agenda, looking to get a remote and power supply unit, as well as check the fuse it uses. I noted eBay parts to give me an idea of the internal designs even before pulling the TV's chassis.

 

Audio did also work while my signal was coming through. 

Previous HD 'Ready' repair also required a new AC adapter, in that unique case, a cord direct to set was not used, but rather an in-between Transformer box that had to be specific 24volts and 6 amps. If you were unaware of that, you'd buy the wrong adapter from eBay sellers because the set is actually marked for the spec, and they're offering the wrong adapter at lower 5 Amps. I tried one and it failed to provide enough juice. The replacement failed as well, due to poor build quality, but it looks like no more I'd have to spend then $100 on the parts if they prove to be the main culprit.

(remote needed for brand association)

 

I wonder if you guys do any of your own repairs, do you follow the throwaway society generally? It seems the prior owners just bought a new set to replace this one, it dates to early 2009 for manufacture. The 47LG50 model LG, a rather nice upgrade from my in-use Viore 32" The LG offers three HDMI inputs, VGA, component, USB, and standard composite and S-video.

HiDef tuner also runs full 1080 Progressive. Hoping a PWR box replacement sets everything else in line for operating smoothly. Will let you know if my prognosis pans out. 

It's something of a gamble spending any money on a project like this, but say if the LCD or LED were damaged and you're looking at 30 inches on up, it's gonna be a hefty price tag!!

 

Here we have CNET's take on it, $1500 originally in 2009 dollars!!

http://www.cnet.com/products/lg-47lg50/

Edited April 16, 2014 by BlackListedB