Bad T-con or bad panel??

[Alternet]

Re: Bad T-con or bad panel??

So I gave the tape method a try and the results are quite perplexing...

At first I started with most of the pins taped but the last few. As you would expect only the "good side" lit up.

Kept removing and adding tape until i was just about ready to give up. The most I could get out of the "bad side" was some garbage while the other side stayed lit with picture.

Then I removed a little more tape leaving pins 44, 45, 46 covered. All of a sudden I got a full picture. I thought I had figured it out and it was "fixed".

After a few of the background pics started being displayed I noticed that the "bad side" was a lot darker then the "good side". (See attached picture)

So I went back and removed the tape from pin 44. That cause the "bad side" to be very very bright. (brighter then the good side).

So I went back and moved the tape to pins 44 and 45. That made the "bad side" go back to darker then the good side again.

So uncovering pin 44 made it bright, uncovering pin 46 made it dark. Seems like the panel works as long as pin 45 is covered.

I made sure that only pin 45 is covered hoping for the best. The "bad side" was still darker then the good side.

So i play around and only cover 44 and leave 45 and 46 uncovered. the "bad side was super bright again"

At this point I was pretty much giving up. I removed all the tape and plugged everything back in like factory, just for the hell of it. Now the "bad side" is still dark but i'm getting full screen still.

I have no idea what is going on. I thought maybe some tape was stuck in the connector or I had damaged the ribbon cable.

I used a magnifying eye piece to verify there was nothing in the connector and I swapped the good side and the bad side ribbons to verify the ribbon was not damaged.

So as it sits on my table fully put back together I have no modifications at all and a full picture but the "bad side" is darker then the "good side". I also noticed that there is ghosting or a fading effect on the on the "bad side" when using the tv menus but didn't get a chance to check if it has any with a video (or if that is how the menus should look when appearing and disappearing.

So i'm not really sure any more if the screen is damaged. I would think that if anything is being displayed on the "bad side" then it has the capability to display what ever its being told to display.

You could also look at it and say one of the colors is not working and thats why its dark but the colors look right. They are just dark so the R, G and B have to be working. As well when covering pin 44 the "bad side" gets very very bright.

So i'm at a loss. Would a bad panel present like this? or should I be looking back at the t-con board?

[nomoresonys]

Re: Bad T-con or bad panel??

^ Yeah...what he said.

[rccrasher65]

Re: Bad T-con or bad panel??

I checked them for shorts (none found) but I did not ohm them. I'll check that tonight.

panel shit the bed!

[nomoresonys]

Re: Bad T-con or bad panel??

Well I thought it was a panel problem.

[Alternet]

Re: Bad T-con or bad panel??

use whisky tape the thin one to cover the first 3-4 pin on the defect side ribbon ..
you may try more pins to cover or less till you have satisfied picture better than to rubbish the panel

Do you have any detail as to what this does? How does blocking some of the signals lead to a full picture again?

[Diah]

Re: Bad T-con or bad panel??

sorry not quite sure what you mean?

use whisky tape the thin one to cover the first 3-4 pin on the defect side ribbon ..
you may try more pins to cover or less till you have satisfied picture better than to rubbish the panel

[Alternet]

Re: Bad T-con or bad panel??

now you don't have to lost play with tAP cut or whisky tape on the defect side as nomoresonys suggest... who knows you could have satisfied picture

sorry not quite sure what you mean?

[Diah]

Re: Bad T-con or bad panel??

now you don't have to lost play with tAP cut or whisky tape on the defect side as nomoresonys suggest... who knows you could have satisfied picture

[Alternet]

Re: Bad T-con or bad panel??

So looks like the screen is damaged but I thought I would update for anyone that comes through with similar issues.

I was asked to take pictures of the screen with each ribbon cable unplugged. (Pictures attached)

As well I took the tv apart again to look for any new damage and found what some what looks like breakages to the screen as well as a black spot that looks like shorting.

strangely it looks like the damage to the screen is only to the outer ground layer but clearly its more then that.

Please see attachments for further clarity.


Further to that the buzzing sound from the t-con board was only happening when the bad side was plugged in and the sound was coming from the main processor on the t-con board or the CM508 chip (I couldn't tell which one)

[nomoresonys]

Re: Bad T-con or bad panel??

Well the tape thing is easy to try, might not work if it's not the issue tho, diah might be right about tcon or ribbon cable issue causing the noise, I didn't read where there was noise til it was pointed out, which would also cause display problems like you have, could test the tcon voltages I guess, which some tcons are easier to test than others. Thinking most times when tape works there isn't any noise coming from the boards.

[Alternet]

Re: Bad T-con or bad panel??

No expert BUT I don't think a graphics driver is the fault.

So you don't think this is a T-con issue?

[nomoresonys]

Re: Bad T-con or bad panel??

Ok, that's much better analysis.

[Diah]

Re: Bad T-con or bad panel??

OP https://www.badcaps.net/forum/showpo...44&postcount=8

Panel show half side clear white by just one ribbon connected by time on both half. never seen till today thats panel or TAP or what ever..
he hear puzzel.. this mean short at ribbon or sockets or T-COn self.. either if there are some strange material full down on the tap during remove the panel make short at smt partss.. all above points easily to inspect.. one by one to clear the issue.

[nomoresonys]

Re: Bad T-con or bad panel??

No expert BUT I don't think a graphics driver is the fault.

[Alternet]

Re: Bad T-con or bad panel??

Your other post indicated you saw the LG logo flash. You likely damaged the panel removing it.

Well I cant rule that out. I just wasn't sure if the new buzzing from the t-con board meant that it was a t-con issue.

The fact that i got a picture when one side is disconnected and i get garbage image when the other side is disconnected and black when both sides are connected seemed like a graphics driver problem to me. (or maybe i was just hoping it was lol)

[nomoresonys]

Re: Bad T-con or bad panel??

It can work for other than double, the way I read one of your posts above is there was a distorted image on one side while doing the one ribbon test.

[neilc6]

Re: Bad T-con or bad panel??

Your other post indicated you saw the LG logo flash. You likely damaged the panel removing it.

[Alternet]

Re: Bad T-con or bad panel??

"Tape method" might work, example there, not in English but self explanatory, there's a ton on youtube, quite a few that involve cutting but I think this is easier and it's reversible, sometimes have to play with size and location of tape, needs to be done carefully ribbons can be delicate, it's done on the bad side with the faulty display of course: https://www.youtube.com/watch?v=Ug7FsUSQpfY

the tape method mentioned here is for a double image is it not? Would this work for no image at all? (as i'm getting no image at all when both ribbons are connected. and also getting a buzzing that sounds like its coming from the t-con board)

[nomoresonys]

Re: Bad T-con or bad panel??

That does NOT prove there isn't a panel fault.

[Alternet]

Re: Bad T-con or bad panel??

i just saw the photo...
do you removed the panel before?? so you may damaged it ??
ribbon need under good loop to inspect the pins of it from both sides.. good loop and light. don't trust only your eyes or glasses

I did remove the panel to fix the backlight issue. But I never saw an image even with the flashlight test before I took it apart.

I don't see any damage when inspecting the screen but i can't rule out that the screen may have bent to much or something along those lines.

could you show us photo on one ribbon disconnected at once

I can take a picture tonight if you would like