Samsung UN46D6420 Horizontal lines, now No Picture

[Agueybana]

Hi everyone,

My TV develop some horizontal lines in the top 1/3 which appear for 3 days before the image just went completely out. I still have sound and black light just no picture.

No visible damage on any of the components, will have to wait until Wednesday for a multimeter.

Thinking it might be a bad T-con did some basic troubleshooting. I manage to get half of the image on TV if I unplug the left ribbon (right on pic) on the T-con.

Suggestions are welcome.

Thanks,
CG

[deasam]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

I have the same HDTV and the same problem, did you find the cure? Was it the T-con?

[Glitcher]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

Looks like a bad panel

[budm]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

Double image like that I would check the tab bondings.

[Ritter2009]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

Did you find a solution to this. Was it the t con board? Please if you have any info please message me. I am having the exact same issue

[tibimakai]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

Mine shows only baclight. If I remove one of the ribbon cables going to the panel, half the screen will show image. The other side shows some wide white and wide black vertical bands and in some area thinner lines which seems to change the color with signal.
In my opinion the panel is bad. T-con boards are around $100.
I have checked the tabs and they seem solid, no change on the screen, if I touch them.
I'm expecting a confirmation from the more experienced technicians too.

[tibimakai]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

Any input please? I have a bad panel or bad T-con?

[Skipfinder]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

How can the panel be bad if it's possible to get half the screen to display normally? Doesn't that speak of a signal to screen error?

[tibimakai]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

But only shows up, if I unplug one of the ribbon cables.

[Agueybana]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

So in my case it was the panel itself and not the T-con I was hopping to be. If looked from an angle the panel has a huge spot where the lines originate and the burn in comes out. I gets extremely hot, I tried the bonding and T-con and this didn't affect the image. Looking into buying a Panasonic Plasma soon have it narrow down now.

[freakaftr8]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

Good choice. Panasonic plasma imho are hands down the best. Your tvs hot spot is a ribbon ic going.south. its basically melting the ribbon cause of a dead short. Seen it before in samsungs unfortunately.

[tibimakai]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

I have picked up this TV to repair it, so I don't know what kind of symptoms had previously.
When I turn it on, I can see some thin black horizontal lines flickering at the top of the screen(upper 1/3 area) and they all disappear and only the backlight stays on.
How can I be sure that the panel is bad? I would try another T-con board, but they are over $100.

[Agueybana]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

I did an elimination process and check T-con for conductivity. From researching when it goes bad there is a particular resistor that goes bad on them.

Can't verify the panel but with the burn marks on mine I can confident said that was the problem after checking other components.

From freakaftr8 response I would imagine that those IC ribbon are behind the black tape around the screen which I was going to removed but decided not to. After all they are probably bonded and not solder so is something you can't fix. Thinking of removing it now with this info just to take a look but don't feel confident it can be fix.
I might take pics and added them if there is physical burn damage on the IC ribbons as I suspect. I boxed yesterday oh well.

[tibimakai]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

Next time I will take it apart I will look closely for burned tab ribbons.
Which resistor should I check on the T-con board?
Any input, Tom, Bud?

[Agueybana]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

It's actually a 5amp fuse on the T-con above where the main ribbon connects.

Reference Post #7 in that thread
http://www.avsforum.com/t/1252060/ca...th-this-lcd-tv

Read about it in other forums as well.

[tibimakai]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

About the fuse, I know, I thought that is something new that I didn't know about.
That fuse is fine, since I can turn on half the picture, by removing one of the ribbon cables going to the panel.

[tibimakai]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

I have played around with this TV today and I have managed to get a nice clean picture out of it, but there are horizontal thin line across the whole screen.
They are more visible at the top then at the bottom, so gradually decreases the intensity of these line toward the bottom.
The way that I have managed to get a picture, I have played with the T-con connector ribbon cable. In a slight angle the picture shoed up and then I have flipped over the retaining tab(same as the panel ribbon connectors).
TV works great, even the 3D feature, but those lines are visible.
What could this be?

[tibimakai]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

I have tried the tabs last time and they didn't change the picture.
I had a while ago, a Sony TV with horizontal thin lines and by replacing the T_Con board, it fixed the lines. Could it be the same problem here too?
Here are some pictures:

[tibimakai]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

Any ideas?

[tom66]

Re: Samsung UN46D6420 Horizontal lines, now No Picture

Uniform patterns like that usually aren't caused by the panel but you can't be sure if it is main or t-con.