Samsung LN52A550 Vertical Lines on 1/3 of Screen

[debom3]

Hello Guys (& Maybe Gals),

I am very, very new to this forum. Found it while searching and trying to figure out what is wrong with my Samsung LCD TV. I never could find a definitive answer, so I was hoping I could ask some experts. Ill try to give as much information as I can. I am fairly mechanical, but am not very experienced with electrical items.

Recently, 1/3rd of the screen has been showing vertical lines that are the color of whatever is on the TV. The problem shows up after about 2-4 minutes after the TV is turned on (The TV looks great for the first 2 -4 minutes) I tried re-seating the TCON flex cables that go and from the TCON board. This did not help (or make the problem worse). Please note that it is not 1/2 of the screen. Its maybe 3/4 of the right half of the screen.

I visually checked all capacitors in the TV that were visible upon removing the back cover. They all looked fine (none were leaking or bulged). Nothing else looked abnormal in the circuitry.

Model is Samsung LN52A550P3F

Here are a couple of photos of the screen.




Sometimes, the 1/3rd of the screen that is affected will just turn black and stay black....


I removed the TCON, as I am hoping that this could be my problem.
TCON Board is FHD60C4LV0.2


What do you guys think? Is the TCON bad, or is my screen toast????

Thank you in advance. I really appreciate any input others may have...

[tom66]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

Tab bonds.
Budm has repaired two similar sets using 52" Samsung LCD panels.
https://www.badcaps.net/forum/showth...udm+52+samsung

[debom3]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

Tab bonds.
Budm has repaired two similar sets using 52" Samsung LCD panels.
https://www.badcaps.net/forum/showth...udm+52+samsung

Thank you so much for your response...
So this looks like something repairable? I am not entirely sure what is fully entailed with a tab bonding repair. Is there a more detailed DIY somewhere that shows how to remove the outer plastic bezel and remove the metal frame on the panel?

Is my understanding below correct??? Basically I need to place the silicone thermal pads on top of the tab bonds like in the picture and reassemble??? Sorry the text is hard to read, basically it just says "place silicone thermal pads here?"



Again, thank you so much!

[tom66]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

Budm is the best with these repairs. If you chant his name three times he may show up. But what you've done looks OK. Just do not run it without the frame for longer than a few minutes as the tab bond ICs (source drivers) run very hot and they are not replaceable.

To diagnose the problem you can apply slight pressure to each bond and see if it gets better.

I'm fixing a 26" ChiMei LCD panel with the same fault right now.

[debom3]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

So I got it all apart last night, man that was a pain. Lots of screws. It was hard to keep track of them all. When I was done putting it back together, I only had 4 left over!! hahahaha

I found the faulty tab. Once it was apart it was fairly easy to determine which one was bad. I found that it was EXTREMELY sensitive. If I just put the pads on this TAB bond, I had 2-5 very skinny veritical lines through the screen. If I did not put pressure at all, I had the same symptoms as before where the colored vertical lines are on the right 1/3rd of the screen.

In the picture below you can see the skinny vertical lines and the large colored vertical lines on the right 1/3rd of the screen. This was my first attempt at reassembly.


Heres a picture of the foam pads I used to put pressure on the TAB bonds.
On the one that was EXTREMELY sensative, I used electrical tape to hold the TAB bond in the perfect position that did not put pressure on the bond itself, but laid it flat so it made a good connection.


It was working for an hour or so after I finished and then I went to bed. I hope it continues to work!!!

Thanks again TOM for the help.

[skienstein]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

Hello there. This question is for Debom3. Unfortunately, I bought this tv through a craigslist ad. I went to check the tv and when I saw it, the picture was flawless. Needless to say, I got it home turn it on and after a few hours, the vertical lines started showing up.
I open the back, reaseted the t-cons and worked for a few minutes until the lines returned.
Being looking at your threads, and it seems that you were able to work out the solution without having to buy super expensive thermal pads like tom and budm.
Where did you get those foam pads? Are they heat resistant? Did you just placed them on top of each tab or did you attach some sort of adhesive?
did it keep working after your repair?
thank you so much in advance!!!

[debom3]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

Hello there. This question is for Debom3. Unfortunately, I bought this tv through a craigslist ad. I went to check the tv and when I saw it, the picture was flawless. Needless to say, I got it home turn it on and after a few hours, the vertical lines started showing up.
I open the back, reaseted the t-cons and worked for a few minutes until the lines returned.
Being looking at your threads, and it seems that you were able to work out the solution without having to buy super expensive thermal pads like tom and budm.
Where did you get those foam pads? Are they heat resistant? Did you just placed them on top of each tab or did you attach some sort of adhesive?
did it keep working after your repair?
thank you so much in advance!!!

Hi Skienstein,

First off, YES the tv is still working great. I actually watched two movies last night on it. It gets used every night for atleast 2 hours minimum. If I had to guess, I have atleast 40-50 hours on it since the repair.

To answer your questions, I used a vinyl foam tape similar to the one in the link below. I had some of this stuff laying around and since I had my TV all a part, I was impatient. It is rated to 200 deg F, which at the time I thought should be good. If I had to do it again, I would use the silicone pads and have the peace of mind that what I used was rated to a higher temperature.

The tape I used that is similar to the that in the link, has an adhesive side and I was able to stick it directly on the tab bond itself. Once the TV is assembled together, The metal frame presses on the foam pad, which puts a little contact pressure on the tab bond ensuring good contact.

One thing I had to do for my uber sensitive tab bond was put a piece of electrical tape on the bond, then I put the foam tap on top of the electrical tape. I talked to a local TV repair guy who said he has had some success with superglue although I didn't really like this idea.

I think the idea is that you have to make these bonds contact when they come a little loose.

http://www.grainger.com/Grainger/Sea...130711151417:s

NOTE: The seal tape I used was 1/4" wide and about 1/4" thick as well. The one in the link is 1" wide....


Keep me posted on your progress and post some pictures. I hope you can get your TV working again!

[skienstein]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

Wow, thanks for the quick response and detailed explanation. I will probably start working on it sometime in the middle of next week. fingers crossed. I will definitely keep you posted!! I really appreciate it!!!!!!!!!!!

[skienstein]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

Hello Debom3. Just a couple more questions before diving in.

I see that you placed the tv flat on the floor. Did you find its better to work flat rather than leave the tv with the stand and work on it standing up? I'm a bit worried about the back of the tv being open and laying the tv down were something might get crushed or shifted without the protection of the back cover.

Oh and can I buy those foam pads out of a regular hardware store like Lowes and or Home Depot?

Thanks again for your time!!!!
Best Regards!

[tom66]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

It's often difficult to service Samsung TVs with the stand still on because it usually goes mostly into the back plastic frame not the actual chassis.

[debom3]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

You can see in two of my pics that I laid the tv face up resting (balancing) on two cushioned chairs. This allowed me to access the front and back at the same time.

I really didn't know what I was doing, just kinda worked with it as I went. It was fairly difficult but take your time and make sure it's good before you put it back together lol

[skienstein]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

Ah that makes sense. I want to start working on it so bad but unfortunately, it wont be until the middle of the week. Thanks again!!!

[skienstein]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

Hi again. I'm almost done removing the bezel but i'm stuck with these wires. they are connected to this board and i can't remove them.
Also, once i remove the bezel should i turn the tv over to work on the tab bonds and also be able to see the picture better?
Thanks again and again. lol

[tom66]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

Press clip down, pull cable out -- don't apply too much force and don't tug on the wires.

You should work on the tab bonds from the top, looking at the display panel.

You need an area 2x as big as the TV to work on it.

[skienstein]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

ok i have it face up. i didnt have to unplug the wires. just put the frame to the side with wires attached. i have a rubber with adhesive that stands up to 176 degrees farenheit. it was the only thing i could find. i do have electrical tape that stands up to 220. should i just use the electrical tape instead of the rubber?

[tom66]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

Rubber works best. Tab bonds run around 150~160 F.

[skienstein]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

yea i put the rubber like you had your foam. probably 1/4" high on all bonds. it wouldnt close cause the rubber was not as giving as the foam i guess. i cut it in half, put the metal frame and it was still giving me the lines.
i took them all out and started to push each one individually. the middle right is probably the culprit. i put the rubber and secured it with electrical tape and it works but i get a single line now that i can't get rid off.
i reseated the t-con again and pressed the other connections, but nothing.
any advice?

[tom66]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

Can we see a picture of the issue?

[skienstein]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

thanks for the help tom66!!!!

[tom66]

Re: Samsung LN52A550 Vertical Lines on 1/3 of Screen

I'd try reseating the bonds but it might not be possible to get rid of that line if damage has been done to the bond :/. You can see in one of deborn3's pictures that they had an issue with stuck vertical lines, and reseating the bonds further fixed it. Just be very careful not to damage the bonds or screen.