Question about LCD TV Repair

[poopdeville]

Hey Guys (and Girls) I am asking a question on behalf of my Brother-in-law. Now I would like to note that He nor I know very much about TV's at all, so please try to elaborate on your answers if you can.

Now, first to explain what kind of TV we're dealing with:

Sony Grand WEGA
LCD Projection TV
KF-50E200A

It's a 50 inch rear projection Television.

Now, here's what happened:

My brother in law purchased this TV a few years back and recently it ran into some problems (which will be explained below). Luckily he had a warranty and exchanged for a new (better) flat panel plasma model. Now, for whatever reason the company he purchased from never took the old TV back.

Now the problem he encountered was this: On the top of the screen there is about a 2-3 inch thick horizontal transparent red tint or line, and along the bottom there is one that's basically the same but it's green. Now I have limited knowledge but I assume this is something to do with the "lamp" or whatever (although I could be completely wrong). Other than that the TV runs fine. If it's not widescreen mode you can barely even notice. So I guess it works fine now, but is probably a bit of a time-bomb.

Anyway my question is this:

1. What exactly is the problem?
2. How much would it cost to fix (assuming it is fixable)

As I said, his TV has already been replaced so if the costs isn't too much to fix he'll probably just fix this one (after all even though it's an older model it is 50 inches and goes up to 1080i ). Obviously if it's too much work and / or money he'll just scrap it when it dies.

Hope to hear some replies, thanks all.

A repair seems kind of unlikely to me, unless you have some experience (or are willing to get some) in dealing with electronics. And I don't mean just learning how to hook up a TV.

Basically, inside the TV, there is a "computer" chip that "contains" a grid of connections. Each connection controls one pixel on the screen. Now, because you're seeing lots of pixels affected, it indicates to me that this is going on on the "input" side of that chip. As David suggested, maybe there is some dirt laying across some of the connectors. You have a minor short circuit somewhere in there. It might even be tin whiskers...

http://en.wikipedia.org/wiki/Whisker_(metallurgy)
http://images.google.com/images?clie...N&hl=en&tab=wi

One possibility to consider: what kind of cabling is your bro-law using to connect the TV? I had a somewhat similar problem with an old monitor because the one of the four color cables was vaguely broken. If it wasn't in the right position, the whole screen would turn a different color. (The fact that it isn't the whole screen makes THIS exact solution unlikely. But you know it's somewhere between the input to the TV and the "grid")

If you and your bro-law are adventurous, you can try to fix it yourself. Get some pairs of rubber gloves, carefully take the back cover off, and follow the wiring from where your "input" cables go. Spray the thing with compressed air, and look for whiskers growing on stuff. If you find a whisker, you will have to use pliers to pull the whisker off. Make sure you're wearing the rubber gloves for this operation. (They're probably unnecessary if you don't touch any other electronic components while doing it -- a la Operation -- or if your pliers have rubber grips. But for safety's sake, keep them on. I'd hate to hear you got a nasty shock.)

Oh, and another suggestion: if you sort of think as the wiring as a "map", stay away from the power supply. Things get more dangerous to deal with safely, the closer you get to it. You don't need to go to your city's power station to find the subway, just because they are connected. (On the other hand, you COULD, if you wanted to, because they are connected)