Help with Samsung LCD with multi colored lines?

[AGeezy]

This is a great forum which I have used in the past to help me fix a capacitor issue with this same TV. I had to replace a couple of them to fix the power up issue that is so common with these 4-5 year old Samsung LCD's.

It has been working fine since my first fix but recently it has developed a couple funky lines. One that is about 5 pixels wide and goes up from the bottom left side to about the middle of the screen and the other is 1 pixel wide right next to it.

I am trying to narrow down what it could be? It sounds like based on others with the same issue it's the t-con card or maybe the Lcd panel?

I was hoping someone could assist me in troubleshooting before I buy any parts?

What I tried so far and some possible clues below:

1. I tried hooking up a laptop and put on a YouTube video that flashes a bunch of random colors fast. When I did that it made the lines go away when certain colors were displayed but did nothing for the overall issue.

2. It does not matter what input it's on or if I am in the tv menu the lines are always there.

3. One thing I think that's interesting is even with the tv off and the power cord removed I can see where the lines are on the black screen. In that same spot where the lines are it's a darker color almost like that area is dead?

4. And of course I beat the tv a bit but that did not do anything but make me look like a fool when my wife walked in.

I can post some pics if it helps. Just hoping someone can lead me in the right direction with this. I feel like I have symptoms that could be multiple things?

[tom66]

Re: Help with Samsung LCD with multi colored lines?

Sadly, it sounds like you have a faulty LCD panel. It is very common with Samsung LCDs around that age.

When the pixels do not get correct drive signals (stuck ON or OFF) the crystals in the pixel tend to polarise, causing permanent burn in. This is the only time when an LCD can actually burn in - due to failure of the controller or drive signals. This might explain why you can see it when it is off.

Here is another TV with the same problem I think:
http://www.ebay.co.uk/itm/32in-Samsu...db#ht_601wt_71

[AGeezy]

Re: Help with Samsung LCD with multi colored lines?

Thanks for the quick response!

Just so I understand better would that mean if I replaced the panel which I don't plan on doing it could happen again if the controller or drive signals are bad?

Hopefully that is not a dumb question i am just a noob with TV's.

I would also be curious to know what symptoms you look for when troubleshooting these type of issues? Like what would you look for to point you in the direction of replacing the t-con card vs. replacing the LCD panel?

It sounds like lines on the screen could mean multiple things?

Thanks again this is very helpful!

[tom66]

Re: Help with Samsung LCD with multi colored lines?

In general a T-con (display controller) failure will cause:

- no picture at all
- overblown picture (too bright)
- half or quarter(s) of screen missing
- "digital" noise (see below)
- entirely black screen with just an occasionally randomly lit lines (controller IC failure, possibly due to voltage regulator failure.)

Digital noise looks like random, on-off patterns or repeating patterns. For example, this Samsung LCD TV I fixed I suspect had a failure of one of the DDR RAM chips on the T-con (you can see the faint green bars - ignore the line, that is for the motion demo), I simply replaced the board though and it worked perfectly.

LCD panels need to be connected to the display controller. In order to do this, flexible ribbons are glue-bonded to the top of the panel. (All corners are bonded - but video data only enters from the top in most LCD panels.) These ribbons pass drive signals to the pixels. If the glue ages, the row signals may be lost or corrupt, so you will get vertical lines on the screen.

[AGeezy]

Re: Help with Samsung LCD with multi colored lines?

Very good info to know. I guess I will hold out for a bit before I make a move with a new TV. Is this more common with LCD's? Or is this something that could maybe happen with LED and Plasma's as well?

I attached a pic that shows a couple shots of my TV with the lines.
(Big line on the left, little one to the right.)

Who knows maybe it will help someone in the future who has the same issue.

Thanks again for the help!

[truep]

Re: Help with Samsung LCD with multi colored lines?

What is the panel number? I have a 32" panel .

[Mt.Man]

Re: Help with Samsung LCD with multi colored lines?

Very good info to know. I guess I will hold out for a bit before I make a move with a new TV. Is this more common with LCD's? Or is this something that could maybe happen with LED and Plasma's as well?

I attached a pic that shows a couple shots of my TV with the lines.
(Big line on the left, little one to the right.)

Who knows maybe it will help someone in the future who has the same issue.

Thanks again for the help!

As the LCD panel ages they tend to be more fragle. Just moving and flexing the panel can cause the bonding of the flex cables to the glass to fail. Which causes many of the thin line issues. Even the new thin sets are having this problem because the LCD panel is the complete structure of the TV with no supporting bracing. The thin sets flex to easy or warp. Tough to get a new panel from Samsung right out of the box thats not warped.

LED panel is a LCD panel but with LED back lighting system.

Plasma do develope thin lines usually when a TCP fails, which is part of the panel attached to the ribbon cables.