Davi.p
The service menu photo is blue also. I see no other screen photos on this thread that would appear normal.

If OP can confirm the lights shine blue through the holes on the back then it's settled. I'm only stating this because unless they truly can't tell the difference, they'll end up investing too much time and money into fixing the other issue when backlights also need replacing....

I've never heard such a thing. Blue image is bad LEDs. I've replaced enough of them to spot them a mile away. See the attached photos of the same welcome screen as yours from a tv with good backlights, and the image of a Samsung I had with bad ones.

With the back cover removed and the tv on, is the light you see through the little holes blue, or is it white?...

I was incorrect in saying I taped the right side. The tv was on its back and I was working on the left ribbon, therefore it's the LEFT side that I taped and this is the side with the washed out colors. I may take the back off again and see if taping only one line instead of 2 helps....

After closer observation, because I'm overly thorough, I have found the degradation. The "left" side is more washed out. I noticed it while watching the Roku screensaver and noticed colors were slightly fading as The objects scrolled to the left edge. However, the tape is on the RIGHT side 🤔

Still though, its completely watchable and most people probably wouldn't notice it unless it was pointed out. I see people trying to sell tvs on Facebook that are blue from bad backlights and they say it's working like new 😆...

I actually did not try just one 😆 first I did like 8 of them and you could see the missing lines and I was about to assume that's the best I'd get, then I said "ah well let's try just the first couple". I played Xbox on it last night and then stared at the bright Roku screens for a long time trying to notice SOMETHING but honestly it looks perfect.

Thanks for following along and helping me out 😉...

I had a similar situation with a TCL once before. The screen was blank no matter what I did. I gave up for a while and left it sit in the corner and then one day brought it back out for one last try. This time I actually got a half screen when disconnecting one of the ribbons. I found the pins for clock signals and blocked them and it's been working relatively fine in my son's bedroom since. It has noticeable lines from the missing signals, but from a few feet away it looks normal.

I suggest you keep trying with those ribbons. Also check near the HDMI and inputs for a reset button....

Update!

So I took the bezel off and there are no side or top tabs. I played around with all of the bottom ribbons and there was no change. I unlatched the clip for the right side ribbon and was messing around with it and could get a perfect picture until I tried to latch it again. I placed a sliver of tape on the far left side covering only 2 pins and it looks flawless. I see no lines anywhere and no degradation in quality....

One of the side tabs, correct? I rarely see those on these newer panels. I did push on each of the bottom ribbons but they made no change. I think I'll pop the bezel off and see if there are side tabs....

I plugged it in again with the donor tcon just to double check the lines. What's weird is that they aren't uniform across the screen. Check out the pics attached. How is this possible??...

First and foremost, is your screen actually this blue? Or is this the distortion you're referring to? If it's appearing blue then you have bad backlights. Are you not able to source a replacement board from eBay or elsewhere? Moving the chip from one board to another is much more effort than it's worth, especially if you DO have bad backlights on top of it.

I had a Philips that did exactly what you're talking about. It would not save any changes I made. I would delete the Google account tied to it, reboot or and the account was there again. The tv would also randomly freeze up and...

I thought I had at least one other tcon from a 58" but I couldn't find anything else that fit. I'm considering pulling the bezel off though and checking for side tabs and seeing if pressure on them will affect the lines. I really don't think it's that though, unless the manufacturer had a bad batch of chips or the process of applying them to the panel was iffy. For out right failure though I don't see more than one failing....

Bottom 1/2 of screen*.... I can't see it being multiple bad COFs or bonds though. 1 maybe, but not 2 or 3. I put the original tcon back and it went right back to the original symptoms too, so I definitely think something is wrong with the tcon. The donor I used for testing was from a Vizio 58", and I also swapped all of the ribbons with it not that did not eliminate the thin lines....

So I swapped out the tcon and the image dramatically improved. I still have some single pixel lines across the bottom 1/4 of the screen....

I was just given this tv yesterday and when I plugged it in I was surprised by the symptoms it presented. For starters, it's a 58" and every 58" tv I've picked up, regardless of brand, has ended up being a bad panel. This one looked like a bad panel at first glance, but the top portion of the screen has a full length, solid, good picture. I've never seen a bad panel do this simply because they are divided in half with Left and Right sides, therefore giving a half-good image or no image at all. I may have a tcon to swap into it, but I'm not sure that's the issue either. I haven't opened...

I just got it apart tonight. There are 8 bad LEDs. I Will order a new set and update this thread after I get it back together. Thanks for the help guys!

I may try this. The most difficult part isn't really securing the tester leads into the plug, it's maneuvering this thing. I had my wife help me lay it down on the table and she was struggling to get it up high enough. Diagnostics would be much easier if they didn't require you to remove the feet in order to get the back cover off.. That is purely unnecessary.

I'm pretty confident that it's bad LEDs causing this. The voltage difference would suggest that an entire strip is out, likely due to a single bad LED 🙄...