Samsung LED TV UA40D5000 T-con fault.

[mictas]

Samsung LED TV
Type: UA40D5000
Model: UA40D5000PM
Model Code: UA40D5000PMXXY
Version: AC04

T-con Board:
31T09-con
T315HW04 VB CTRL BD

--Please Read Below for an after comment--

---- I am looking for advice for testing the SMD components on these T-con boards----

So at my local Hackerspace, I have been given a challenge to fix a few TV's with a bit of an issue, with the displays.

Not all the TV's act in the same way, but I have found by switching the t-con boards, I can switch out the display issue, from one to the other.

Buying new T-con boards is an option, however I have been told no on that and to try and repair the t-con boards themselves.

Please note that I did make the problem worse, after applying a hotair from a rework station over one of the boards.

So, I have uploaded a few images, that I had taken with my crappy digital microscope and I am hoping for feedback on testing and replacing some of these parts.

I have a few iffy looking caps.



Please see screenshots, I took from a few videos I made. https://imgur.com/a/MGwrQ


----After this topic----

I have attempted the tape option, now all I have gone is place a strip of tape on both ribbon cables, which lead to the LCD panel.
I have done this to two of the TV's and they each have glitched once through a 20 minute video, each time this happen only after I had turned on each TV.

I am not one hundred percent happy with this and feel that it might not last, but that is how I feel.

[difinity]

What are the display issues you are seeing.
More common on the Samsungs to have a faulty gamma IC.

[wraper]

There is nothing wrong with those capacitors. Samsung MLCC often have rough surface. Also MLCC don't visually show any faults unless there is a visible crack in them.

[mictas]

I looked this one up online and found the image distortion was common, i.e. a part of the screen like from the top and down will shift in color or create a ghost affect in a bar across the screen.

[difinity]

It's only part of the TV, which suggests it's a faulty tab bond between the small board the tcon cables connect too and the panel.
A faulty tcon will affect the whole, unless one of the ribbon cables isn't seated correctly.
The Tcon is at the bottom on these TVs so it's common that someone sprays liquid onto the screen to clean it and liquid runs down the bottom of the screen and corrodes where the cable attaches to the panel/board.
You will have to strip the panel down to see it.

[mictas]

It's only part of the TV, which suggests it's a faulty tab bond between the small board the tcon cables connect too and the panel.
A faulty tcon will affect the whole, unless one of the ribbon cables isn't seated correctly.
The Tcon is at the bottom on these TVs so it's common that someone sprays liquid onto the screen to clean it and liquid runs down the bottom of the screen and corrodes where the cable attaches to the panel/board.
You will have to strip the panel down to see it.

I'm sure, I said something in my first post about playing musical chairs with these TV's and t-con boards and taking one issue from on TV and moving it to another.

Also I am sure there is no water damage on the t-con boards, because one I have looked at all of them and two they are outside of the TV's, I did update the folder from my first post with a new image, so here is one of the t-con boards, they all look pretty much the same.

[SMdude]

I would start by tapping and pressing around the board and see if there is an area that causes things to happen, failing that, carefully heat about the place and see if you can isolate an area and freeze spray(don't use too much or you'll get moisture).

But my gut instinct says that BGA in the middle of the board has a bad contact/ solder ball that didn't flow properly when it was built.

How old are these tv's and how much use have they had?

[difinity]

I'm sure, I said something in my first post about playing musical chairs with these TV's and t-con boards and taking one issue from on TV and moving it to another.

Also I am sure there is no water damage on the t-con boards, because one I have looked at all of them and two they are outside of the TV's, I did update the folder from my first post with a new image, so here is one of the t-con boards, they all look pretty much the same.

[/quote]

I did not say the possible water damage was on the tcon,  follow the two cables coming out of the top of the tcon. How about a photo of the fault ?

[mictas]

I did not say the possible water damage was on the tcon,  follow the two cables coming out of the top of the tcon. How about a photo of the fault ?

That I have not taken that, I was going to try some Kapton tape on the ends, but I did not have the time for it.

I would start by tapping and pressing around the board and see if there is an area that causes things to happen, failing that, carefully heat about the place and see if you can isolate an area and freeze spray(don't use too much or you'll get moisture).

But my gut instinct says that BGA in the middle of the board has a bad contact/ solder ball that didn't flow properly when it was built.

How old are these tv's and how much use have they had?

I have tried applying heat with a cheap hot air re-flow station, over the center BGA on one board and found I made the problem worse.

But still it had an effect!