Dell 34 inch U3419W Monitor with thin stripes on partial screen

[ChristianBr01]

Hello everyone,
I have a Dell U3419W Monitor that has some thin stripes on a part of the screen since Tuesday.
This lines cover about a third of the screen and appear for 2 seconds before disappear for another 2 seconds.
This repeats the whole time. I have not opened the case yet cause I had no time, but will try to fix it on this weekend. For me, it looks like a problem on the TCon... Am I right?
Does someone have seen this before?

[CapLeaker]

Weird for the stripes to appear and disappear every 2 seconds.

[ChristianBr01]

It is weird.
What I already tried is go through Dells suggestions on their website to solve the problem but no changes.
I've changed the ports from DP to HDMI and replaced the cables but no changes.
Tried to reset the Monitor through OSD, change the frequency in Linux and Windows a couple of times with the same result.

Disconnected the Desktop and used my Laptop as Video Source... everything stayed this same. But if you look at the picture,
you'll see that the lines appear as soon as the the panel has to display a picture on screen, even if it's a OSD without a connected video source thru HDMI or DP.
As soon as the screen has a picture to show, the lines appear and disappear in a 2 second cycle.

[CapLeaker]

Yeah, sometimes suggestions are for kinda similar problem, but not it. While a cable can do artifacts like that on a screen, it for sure not every 2 seconds in and out like clock work. Whatever it is, it’s inside the monitor.

[ChristianBr01]

It's definitely inside the monitor. I opened it up and inside it is completely a LG. It was a pain to remove the small ribbon cables from the metal case cause they have been glued to it.
Everything looks quite good but I was expecting the fault an the T-Con and I truly believe that I'm right with my thoughts.The Voltages from the PSU to the T-Con are all stable but the Voltages on the T-Con are not.
I will write them all down and post them here cause I need here some help from someone with some experience.

I've expected some fluctuations and that something is pulling a specific voltage down, but it's the opposite.
As soon as the lines appear, the voltages are going up. Not too much but for example on VCC10 from 1.02V to 1.18V and on VCC33 from 3.304V up to 3.494V.
Voltages go back to normal when the lines disappear.

I will write them all down and post them. For me, as a beginner, it's a strange behavior or am I wrong?

[CapLeaker]

I was wondering about the voltages on the Tcon if there is any indication that the lines and voltages have something in common. Try putting a little pressure on these flimsy thin tab bonds.

[ChristianBr01]

I can't believe. It was a small 0603 capacitor on the pcb where the cof strips are connected to. I couldn't find something faulty on the TCon but had fluctuations on every single voltage line.
PSU was 100% ok and Mainboard too. Had only problems on the TCon board...
I was just guessing and checked all the capacitors there for short circuits. I found a shorted capacitor on the left side.
I removed it with hot air and replaced it with another one from a TV board. Everything's working fine again.

What a strange behavior for a shorted capacitor. Have not expected this... honestly, I was 100% convinced that it's something else but not a shorted cap.

[CapLeaker]

Nice repair!