Samsung 52" LN52A550 - Bad panel or TCON...

[richr69]

I obtained a 52" Samsung LN52A550 which did not initially turn on. The culprit being the power supply caps (blue sam-wha XC series 1000uF 10V), which I fixed. Everything was looking good for awhile. After some cleaning and putting it back together, I connected a HDMI source finally to see some images. After a few moments, right down the middle (left half of the screen) a 5" vertical bar of very colorful lines appeared.

The vertical sets of lines appear in front of anything that is on the screen e.g. menu is behind the lines.

I noticed when I shut the TV off; the screen goes black except for the vertical lines. They stay on for a moment before they go off too.

I reseated all the ribbon cables between the panel and TCON, and the TCON and main motherboard, which did not help.

I'm suspecting panel tab bonding. I touched/pressed all tab bonds and none of them appeared to have any affect.

So I'm looking for some suggestions before I call it quits.

Thanks.

[ReeceyBurger123]

Re: Samsung 52" LN52A550 - Bad panel or TCON...

Thats a bad panel unfortunately

[Alastair E]

Re: Samsung 52" LN52A550 - Bad panel or TCON...

Take the steel frame off the panel and apply pressure where the tab is fixed to the panel.

Sometimes its possible to shim the frame with some thin rubber/silicone heat-pad/sponge etc which can effect a botch cure.....
--This is the only option in some cases it works, sometimes it doesnt...

[richr69]

Re: Samsung 52" LN52A550 - Bad panel or TCON...

Take the steel frame off the panel and apply pressure where the tab is fixed to the panel.

Sometimes its possible to shim the frame with some thin rubber/silicone heat-pad/sponge etc which can effect a botch cure.....
--This is the only option in some cases it works, sometimes it doesnt...

Done that. No luck. Looks like panel is going to the trash bin.

[Hobby 1]

Re: Samsung 52" LN52A550 - Bad panel or TCON...

post a picture of the screen

[richr69]

Re: Samsung 52" LN52A550 - Bad panel or TCON...

Here are some pictures.

1.) Power On
2.) Few seconds after power on
3.) Menu selected
4.) Power Off

[chopdre]

Re: Samsung 52" LN52A550 - Bad panel or TCON...

If the panel is bad, will you be selling the main board?

[budm]

Re: Samsung 52" LN52A550 - Bad panel or TCON...

You may not have put just right spots on the tab, see picture # 2 of the screen shot:
https://www.badcaps.net/forum/showth...ht=tab+bonding
It is very tricky to get it right.
Mine was a lot worst than yours.

[richr69]

Re: Samsung 52" LN52A550 - Bad panel or TCON...

Hi budm,

I did press down pretty hard on the tab above where the vertical ranbow of colors appeared, but that did not seem to do anything.

Just to be clear is the pressure suppose to be on the flat ribbon at the point where it is bonded to the panel or where the driver chip is bonded to the flat ribbon or both? Hopefully that makes sense.

WHen I put it back together, I did place a thick piece of the heat sink matriel about 1/8" thick (kinda rubbery) I grabbed off of a spare board, and place it so that the driver chip was in contact with it. Those screen shots I attached are after I did that.

I guess I will take it apart and try again.

[richr69]

Re: Samsung 52" LN52A550 - Bad panel or TCON...

If the panel is bad, will you be selling the main board?

I'm thinking about it. But, I'm going to take it apart again and give another go at it.

[budm]

Re: Samsung 52" LN52A550 - Bad panel or TCON...

The part where the flexible circuit board is connected to the log rigid green circuit board. You can see those fine conductor traces.
https://www.badcaps.net/forum/attach...8&d=1357462883

[sheen818]

Re: Samsung 52" LN52A550 - Bad panel or TCON...

Hi, Budm, I have a samsung 52" TV with same issue. when TV is cool, have exact same black band as in you picture. after tv is hot, black band disappeared. Do you mean pressure the connection area on the green circuit board?
1)What do you think: if I try to heat it, make the glue melt and solid again.
2)put some rubber between green circuit board and metal frame. I know there is a rubber that can transfer heat. What is the name and where I can buy it?
Thanks.

The part where the flexible circuit board is connected to the log rigid green circuit board. You can see those fine conductor traces.
https://www.badcaps.net/forum/attach...8&d=1357462883

[budm]

Re: Samsung 52" LN52A550 - Bad panel or TCON...

https://www.badcaps.net/forum/showpo...33&postcount=7
BERGQUIST.

"1)What do you think: if I try to heat it, make the glue melt and solid again. " I did not try that since I know the thermal pad so I did want to take a chance and take the screen apart if it does not work.

[sheen818]

Re: Samsung 52" LN52A550 - Bad panel or TCON...

Hi, Budm, thanks. can you give some direction that how to do it. Or you have poster how to deal with these cases. you only put one layer Silicone thermal interface pad or a few layers to fill whole gap between metal frame and green pcd board. need pressure to make it tight? thank you.

https://www.badcaps.net/forum/showpo...33&postcount=7
BERGQUIST.

"1)What do you think: if I try to heat it, make the glue melt and solid again. " I did not try that since I know the thermal pad so I did want to take a chance and take the screen apart if it does not work.