Bad T-con or bad panel??

[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??

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

[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??

Ok, that's much better analysis.

[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??

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??

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)

[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??

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??

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??

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?

[nomoresonys]

Re: Bad T-con or bad panel??

Well I thought it was a panel problem.

[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??

^ Yeah...what he said.

[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?

[Diah]

Re: Bad T-con or bad panel??

did you still hear puzzle?? can you show us picture when cover tape make the defect side brighter?

[Alternet]

Re: Bad T-con or bad panel??

did you still hear puzzle?? can you show us picture when cover tape make the defect side brighter?

There is a little buzz but it more sounds like a buzz from a switching power supply not the loud buzz that I was getting that sounded liked a short.

I don't have a picture of the when pin 44 was covered. but just imagine what it would look like if your cranked up the brightness to extreme levels but only for one side of the screen.

[Diah]

Re: Bad T-con or bad panel??

There is a little buzz but it more sounds like a buzz from a switching power supply not the loud buzz that I was getting that sounded liked a short.

I don't have a picture of the when pin 44 was covered. but just imagine what it would look like if your cranked up the brightness to extreme levels but only for one side of the screen.

also pin 44 are Gama..
at this point you reached i would suggest you dont touch the ribbon socket from panel side any more.. let it work with external live signal for view time as it start from cold state( out from wall sockt ) if the condition remain as ou show us in the photos. not bad at all if you do risk and investment little by replacing T-CON... but no one be sure what the result.. just try.

[Alternet]

Re: Bad T-con or bad panel??

also pin 44 are Gama..
at this point you reached i would suggest you dont touch the ribbon socket from panel side any more.. let it work with external live signal for view time as it start from cold state( out from wall sockt ) if the condition remain as ou show us in the photos. not bad at all if you do risk and investment little by replacing T-CON... but no one be sure what the result.. just try.

How do you know pin 44 is the gama? do you have a schematic for this tv or are you just making an educated guess based on my experimentation results?

If there is damage to the panel could it act like this? I don't have a huge background with lcd engineering but I do have an electronics engineering background. I would think that the lcd pixels are in fact functioning letting or blocking the amount of light through but the thing controlling them is not sending the correct information. (again though I don't have a back ground in lcd panel development so I don't know.)

[Diah]

Re: Bad T-con or bad panel??

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

this is yours when i wrote about tape...

and this bellow now the same way you are attacks some one like to help..

How do you know pin 44 is the gama? do you have a schematic for this tv or are you just making an educated guess based on my experimentation results?
(again though I don't have a back ground in lcd panel development so I don't know.)

you shared your problem over this forum.. and many users over here like to help and they did by sharing their experiences and KNOW HOW.. not to put you at experimentation process.

if this doesn't suit you then do what ever you like. good luck