Samsung UE50ES5500 LED TV bottom third of picture jitters

[dicky96]

A Samsung UE50ES5500 50" LED TV landed on my bench

It's easier to show the video of the problem than try to explain this fault. This is with a static image from MXQ Android box on HDMI

https://youtu.be/N54a1ky3Ka0

I tried googling and also a forum search on here but couldn't find anything relevant to bottom part of screen jittering on LED TV, if that is the correct description.

Apologies in advance if I was using the wrong search terms.

Any ideas? Bad capacitors/decoupling?

Cheers
Rich

[vinceroger69]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

odd fault maybe worth reseating the lvds and tcon ribbon cables i wonder if this set has the panel pcb on the bottom edge of the tv and someones used cleaner on the screen thats ran down and now damaged the tab bonds? only guessing but worth checking i guess. if ok maybe try a little heat aimed at the main ic on the mainboard just incase bad bga soldering.

[dicky96]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

odd fault maybe worth reseating the lvds and tcon ribbon cables i wonder if this set has the panel pcb on the bottom edge of the tv and someones used cleaner on the screen thats ran down and now damaged the tab bonds?

Here are some pics. There are two long narrow pcbs across the bottom. I'm not sure which the lvds ribbons, is that the two from the tcon board to the narrow pcbs?

These connectors look like the same sort I see on laptops where you lift the little black plastic flap to release the ribbon but these don't seem to release the same way?

The 12 ribbons coming from the narrow pcbs are bonded on somehow and they all look clean and uncontaminated

I assume the tcon ribbon is the right angled one from the main pcb with the larger silver metal connectors

Rich

[vinceroger69]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

In your second picture the lvds lead is the top centre black cable some times these connectors can cause issues if dirty and yes it was the bottom two ribbon cable in picture two again sometimes these can give issues if dirty and yes picture one shows the tab bonds but some times its where the lcdis bonded too the panel they get corroded ive only seen this on tvs with the panel pcbs at the bottom of the tv hopefully a more experienced member will advise more.

[dicky96]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

Thanks Vince. What is the correct method of releasing the tcon and lvds ribbons?

It's not easy to see the tab bonds to the lcd panel itself but if these were corroded is that repairable?

Rich

added.
I figured out the lvds ribbon connectors :-)

[vinceroger69]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

i doubt its the tab bonds too be honest and if it was not usually repairable is that panel pcb on the bottom of the lcd panel or top? on the mainboard theres a heat sink i wonder if its worth heating that area and see if picture alters, maybe budm will see this thread and have some advise too offer does the fault show up on all tv inputs or just hdmi

[diif]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

Disconnecting one half of the tcon at a time should rule out the tab bonds. I've seen similar jittering on a Samsung but it was full screen. It was a BGA issue.

[dicky96]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

At the bottom.

Actually not tried other inputs but the owner reported the same problem when they brought it to me and I have no idea what input they were using

At the moment I put it back together somewhat and had a completely scrambled picture on the left side of screen and mostly black from the centre to the right then with some static vertical stripes to the far right side

Reseated the lvds cable again and now have a good picture to the left (apart from the original flickering problem at the bottom) which goes as far as the centre of the screen but I have black from centre then vertical stripes to the right.

I guess I must have not re-seated one of the tcon ribbons properly fortunately I didn't put all the screws back in to the casing.


Rich

[dicky96]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

Got it back working how it was now I reseated the tcon cable for the right side of the screen so at least I didn't make it worse

And I have seen what some of the problems look like with a badly connected ldvs and tcon cable for future reference.

The problem is not related to any particular input, in fact the problem is present as white horizontal lines flickering with no source attached and a blank screen - and obvious on the OSD menu

I tried warming the bga with my hot air station to the point it was uncomfortable to touch the heatsink for more than an instant (but not so hot that it burnt my finger) and this made no difference to the extent of the flickering either better or worse

I generally warmed around the whole main board and it doesn't seem to make any difference either though I didn't apply much heat to any specific area.

I've checked the PSU outputs, they are slightly 'out of tolerance?' There is at least one buck regulator on the main board but i have no data on what the outputs should be. I doubt this is a power supply issue anyway as it affects a specific area of the screen.

5V = 5.25V
13V = 12.76V

All the electrolytics on the PSU look good visually.

What was the method of disconnecting one half of the tcon at a time and what should I see? A blank half screen and a good half with or without jitter depending on which cable? Could this be a tcon board fault?

Rich

[attainteddragon]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

if you get a good pic with one half disconnected but a blank or highly distorted pic on the opposing half, then the panel on the bad/no picture side is pulling down your voltages. could be panel/tab bond or component on the panel driver board.

[vinceroger69]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

has the lcd panel just got the one panel pcb i have seen a few now where they have two one on thetop or bottom plus one on the side, i wonder if its a cof issue (chip on flex issue) i was hoping budm or reece etc may of seen this issue before and advise you.

[dicky96]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

@attainted....
Thanks. OK there is no harm me trying that. However would this be likely as if the panel on the bad side was pulling down voltages wouldn't that affect the whole screen. But it's easy to test an eliminate anyway

@vince
The only ribbon cables I can see going to and from the tcon are the ones I checked. I don't see any cables going anywhere else from the main board other than the speakers, joystick button and LED drive. can't see any other panel pcbs apart from the two across the bottom - unless they are hidden under the metalwork

[vinceroger69]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

its certainly a odd fault but saying that i have seen a toshiba 32 inch set with this sort of issue at the bottom of screen when i was visiting friends earlier, the lines were there on all inputs too, they said they appeard to grow higher over a period of time maybe 8mm high now so they are noticable but there lines dont jitter at all, there solid lines which looks like some sort of panel failure too me.

[dicky96]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

@vince
Funny to mention that as I also think these grow higher over a period of time.

Or like they mark the 'high tide line' and don't clear afterwards if you know what I mean

Rich

[Hamie]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

+1 for faulty panel.

[attainteddragon]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

does the fault present itself over the menu screen as well?

[dicky96]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

Yes it is on the menu screen just the same as with an external signal

[attainteddragon]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

i would be thinking that it is definitely a panel fault then.

[vinceroger69]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

My mates just messaged me and says hes fixed his line issue on his toshiba when i asked how as i thought i was a lcd panel issue he said he put a strip of black insulation tape across the bottom edge of the lcd panel lol i guess thats one way to hide the lines for now haha.

[dicky96]

Re: Samsung UE50ES5500 LED TV bottom third of picture jitters

OK thanks guys. I will give this one back to the owner and not waste further time on it.

Rich