LG 50PX1D - Black Bars on Top

[slawson2000]

I am new at this, but the wife said fix it or get another. So here it goes..

I have some black bars. There all the time. See below.



I have been reading around, but have not quite grabbed the concept yet. I think it is a board. If so which one? Are boards repairable?

Thanks in advance.

[tom66]

Re: LG 50PX1D - Black Bars on Top

Are there ANY pixels lit in the black bars? If so, the panel is bad. If not, you probably have the common issue with cracked solder joints on the SMD resistors on the driver chips, which is repairable...

[slawson2000]

Re: LG 50PX1D - Black Bars on Top

I was hoping you would chime in and tell me something different than you did. It looks like there is some mostly blue haze in the black spots and a couple faint red lines in the non-black areas (to the right of the black spot).

From what you just said, this plasma is a lost cause, correct? If so, are any of the parts sellable or should I just toss the whole thing?

Suggestions/requests welcome.

[johnboy1313]

Re: LG 50PX1D - Black Bars on Top

No, don't toss it. If the panel is bad, which it does look to be, the internal boards are still good. If you have the skill and the patience, sell the boards on eBay. If not, sell the TV on Craigslist for parts.

[slawson2000]

Re: LG 50PX1D - Black Bars on Top

I have plenty of patience (skills are questionable). What are the parts I am looking to sell, and what are they worth? I would much rather see the parts go back into service than to the trash.

Any help is appreciated.

[slawson2000]

Re: LG 50PX1D - Black Bars on Top

Anyone need parts?

[tom66]

Re: LG 50PX1D - Black Bars on Top

Actually, I am willing to bet that I am wrong, and the panel is good, but you have maldischarge (sparklies.) On a normally dark screen, do you see such pixels elsewhere? Panel failures usually manifest themselves as stuck lines.

[slawson2000]

Re: LG 50PX1D - Black Bars on Top

On a dark screen, there are a few pixels that sparkle but nothing like the photos above. Actually, unless you were looking for them you may miss it. There is a faint bluish line across the bottom as well. Neither showed up well on a picture.

[tom66]

Re: LG 50PX1D - Black Bars on Top

Well, it is probably worth a shot anyway, if you want to fix it. You will need to take the cover off & get us pictures.

[slawson2000]

Re: LG 50PX1D - Black Bars on Top

Pictures are not a problem. What do you want pictures of?

[tom66]

Re: LG 50PX1D - Black Bars on Top

One of the overall chassis for now, we can indicate where we need you to look from there.

[slawson2000]

Re: LG 50PX1D - Black Bars on Top

Not the best picture, but it should be a good starting place.

[slawson2000]

Re: LG 50PX1D - Black Bars on Top

And the next step is... ?

[tom66]

Re: LG 50PX1D - Black Bars on Top

Sorry. Got sidetracked and missed your post.

https://www.badcaps.net/forum/attach...1&d=1366119703

Along the right of this image (top of TV) the orange connectors are the suspects. Turn the TV on and try to locate which ribbon the bars affect. Then turn it off and unplug the suspect ribbons. (Do not unplug them while the TV is running.)

Once you have located those ribbons, you will see some resistors on them. Apply new solder to each end.
http://ww2.justanswer.com/uploads/bl...032314_cof.jpg

[slawson2000]

Re: LG 50PX1D - Black Bars on Top

I am not sure I am looking in the right place. Where should they be?

[cliff_hootarski]

Re: LG 50PX1D - Black Bars on Top

The aluminum bar with the "WARNING" sticker is the heatsink for the "COF". Under the heatsink should be an IC and maybe resistors. You can see from your picture the film ribbon cable going from the connector board to the panel.

[slawson2000]

Re: LG 50PX1D - Black Bars on Top

Found them. They "look" okay, but... Now do I add solder or just re-melt what is there?

Is there a way to test them?

[cliff_hootarski]

Re: LG 50PX1D - Black Bars on Top

Please take a picture.

[slawson2000]

Re: LG 50PX1D - Black Bars on Top

Per your request....

[cliff_hootarski]

Re: LG 50PX1D - Black Bars on Top

Now, is that a picture of the COF that corresponds to one the black bars (those are the ones you need to concentrate on)? I would assume under each rectangular pad is an IC. Hopefully the IC's are good. The only set I have any experience with was an rebranded LG with no resistors and the IC was bad leaving a rather large black vertical bar. (could not repair)

Tom referred to adding/resoldering the resistors (marked with 100). It would be a rather delicate operation with that thin film! Of course you've got nothing to lose.