Just picked up a 55 inch LG 4k OLED for $50!

[tom66]

Re: Just picked up a 55 inch LG 4k OLED for $50!

Indeed. Also I don't think they can produce plasma subfield upon oled dur to the fact that oled is going flexabe.

Now that presents another conundrum if this technology is so finicky and dangerous like if it gets punctured, If it stays alive wont it act somewhat like a lithium ion battery when punctured?

I only ask because now on to the bad panel..

When I was scoping the current draw between the good panel and the bad one, the Vertical lines on the right hand side I noticed that there is a significant current draw at the 1.8v. Is this not VCC? These are the capacitors. I posted the picture earlier Of the capacitors on That I noticed were darker. That section is reading 84ohms. On the good panel it reads 250ohms. I removed those capacitors and I get 50 ohms. I put them back because the good side measured 84 ohms also. Whatever I replace or remove on the bad side changes the reading on the good side also. I'm confused. They must be linked together inside the panel somehow as the board on the right is separate from the left. The right farthest COF driver is obviously shorted. If I remove 12 V to tcon, The TV will state powered. And soon as I Introduce the 12 V back, The TV does something odd I can see a horizontal line withiin the vertical lines scroll from top to bottom of the.panel. As soon as that line reaches the bottom the TV shuts down. With the capacitors removed and the TV only reading 50 Ω on that section, When I power up the TV it immediately shuts off without displaying anything. With the capacitors in place and the 84 Ω reading the TV will stay powered up until this scroll line reaches the bottom of the panel.

I know this all sounds confusing but this is what I am seeing.

I suspect that the panel may scan for faulty drive lines if that is what you are seeing. In other words it is checking the integrity of the panel before it fires it up.

If you puncture the panel you will probably find you end up tripping some integrity sense mechanism. Maybe it will shut down right away. I don't know.

Did it look like this?
https://www.youtube.com/watch?v=npRGfsFFf3M

[tom66]

Re: Just picked up a 55 inch LG 4k OLED for $50!

So it is the TFT (driver), not the actual Light Emitting Device (OLED), that causes the retention.

That would be my suspicion if it can be erased like Freak indicates. Of course, the OLED pixel itself can still be damaged over time degrading its output.

This is interesting, because it is the same as plasma TVs, which can get both temporary image sticking and permanent burn in, the latter being much less common.

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

Yes Tom exactly like that. Although that when you can clearly see a crack in the screen, mine is not cracked. And that's scan makes it all the way to the bottom before shutting off unlike this one found the crack and shut off immediately. Maybe it is just coincidence that it is shutting down after the scan

[budm]

Re: Just picked up a 55 inch LG 4k OLED for $50!

That would be my suspicion if it can be erased like Freak indicates. Of course, the OLED pixel itself can still be damaged over time degrading its output.

This is interesting, because it is the same as plasma TVs, which can get both temporary image sticking and permanent burn in, the latter being much less common.

I see Plasma screen with Phosphors burn-in just like regular CRT when we get them from company that use the PLASMA as signage (showing still image all day long) which is not the same as image retention problem.

[tom66]

Re: Just picked up a 55 inch LG 4k OLED for $50!

I see Plasma screen with Phosphors burn-in just like regular CRT when we get them from company that use the PLASMA as signage (showing still image all day long) which is not the same as image retention problem.

There's actually multiple reasons plasma screens get burn in.

The original issue was phosphor degradation but that is not an issue in all but the most extreme cases. The phosphors on modern plasma panels were very rugged.

The most common reason is the pixels themselves degrade because the high-energy ions damage the MgO coating on the cells. The MgO coating is vital to provide the discharge energy for the cells (it is what produces the electrons when stimulated with the set-up ramp energy, and it forms part of the cells memory.)

Temporary image retention is caused by charge sticking on the cells, due to the MgO. As panel efficiency improved the MgO coating was made thinner and thinner. This had the downside of increasing image retention and burn in issues. This was combined by the minimal reset ramps targeting very low black levels. Usually such retention was reversible, but it takes quite a while (100+ hours).

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

So this system detects a shorted COF and will not allow the panel to display after the residual scanning for shorts/cracks. The only saving grace here is that I find a way to mimic the system to think there's not a problem or disable that portion and it looks like it comes from the tcon. If I remove the wider LVDS cable the TV will come on and stay on with a Gray screen. As soon as I reconnected the LVDS it goes in the shutdown.

Now the TV will also shut down if the panel is not connected to the tcon. I wish I could find a schematic for the tcon so I may be able to mimic signals processed to the main board to tell it to stay alive in produce the image.

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

Well panels toast. As I was probing voltages and scoping drive return signals back to mainboard, that area with the lines gets hot when data is being fed to that source driver. Well when I turned the tv around, there was a crack in the panel, right there on the bottom right where the issue is.

Guess it overheated... lol

needless to say I'll throw it in storage, maybe I'll get lucky and find another panel, but my find was probably like one in a million.

Thanks for all your help on this thread guys this has been intriguing. At least I got one good working tv out of this adventure.

P.s. Tom66, I went ahead and stabbed the panel since I had nothing to lose and you are absolutely correct the system trips an overload detection and it will not even allow the oled to power up. Pretty ingenious system. 2 different functions and systems sandwiched in one pane of glass working in conjunction.

[tom66]

Re: Just picked up a 55 inch LG 4k OLED for $50!

Ah man you idiot

Nice TV you had there.

I'm keeping an eye out for a cheap OLED with burn in, that might be fixable...

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

Doh!!�� I still can't believe the panel cracked. I pulled up the bottom of the panel and that end COF was completely melted!

[Moreno83]

Re: Just picked up a 55 inch LG 4k OLED for $50!

Pfff , that is really sad. Sometimes you need to leave things alone haha. And yes i also learned that the hard way.......

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

Understand that I do still have one perfectly working set with the panel that I ordered. So the one had the line in it is the one that is cracked. So I'm not really out anything except for a panel that didn't work to begin with that is now worse.

Now I just need to find another deal with a return from Best Buy for vignetting or something like that and I'll be set.

I wonder how I can get my hands on an RMA? lol

[mmartell]

Re: Just picked up a 55 inch LG 4k OLED for $50!

Curious if you contacted the seller of the "new" panel about it not being new ?

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

I did however since it straightened itself out in an "image cleaning phase", I'm not worried about it now.

The seller was just a re seller on eBay where I came across them and so since they thought it was new it's not a big deal. They had no way of testing it prior to selling and I don't even know how they got it.

It's not like a deal like this comes around All the time. So with my perfectly good working im probably like I said gonna keep it.

The broken one however I just need to find another panel now that I have all good boards. It would be cool to have as another set in the house.

[RJARRRPCGP]

Re: Just picked up a 55 inch LG 4k OLED for $50!

Imagine someone getting pwned with image retention via someone else seeing private information being retained!

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

Right!

[kevlar51]

Re: Just picked up a 55 inch LG 4k OLED for $50!

Not trying to threadjack, but I'm having similar issues with my 65eg9600-UA. I've been attempting to upgrade it to a 65eg9600-UB (the UB models allow HDR via HDMI, whereas the UA models do not). I got a UB T-con and UB main board from ebay. I swapped them out, and got a "no signal" picture, but half the screen was black, and no inputs worked.

Re-seated all the cables, and tried again to no avail, and basically got to the lockout you discussed, where I'd only get the flashing LG logo.

Swapped everything back to original configuration and everything was back to normal.

To try again, I ordered an LG service remote (model 105-201m knockoff) from Amazon for $12, along with some new cables (my original T-Con had the long cables you noted, and the new T-con only needed the short).

Next attempt didn't get me anywhere, and it stayed in lockout mode. Then I put my old UA mainboard back in to try with the new T-con (troubleshooting to see if the T-con or the mainboard was at fault, since this T-con model # works with both UA and UB, but my old one doesn't). It worked, but looked much worse than my old configuration; there was a lot of splotchy banding and a washed out spot in the upper right.

So I went back to my original configuration. Started it up, it turned on as normal for about 5 seconds and then shut off. Tried again a few times and then got stuck in the lockout mode described earlier in this thread.

I found this thread sometime today (so I'm hoping that's lucky). My service remote has all the buttons you were mimicking with the .wav trick (and includes IN-STOP), so the power_only button will get me out of lockout, and for the briefest second will tell me to hit exit and in-stop. If I do that, the screen turns white, but nevertheless shut down.

Here's where I'm hoping the experience you guys gained earlier this month can help me--any clue what my next step should be? Is my original (and perfectly good before today) T-con fried? Or is it my main board? I'm hesitant to check with my UB t-con again before I have more clarity on what might have gone wrong.

Thanks very much.

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

Having quite a bit of experience with this particular model be it the 55 or 65" you've come to the right place!

1st of all you are running your original UA main board and UA tcon correct?

[freakaftr8]

Re: Just picked up a 55 inch LG 4k OLED for $50!

I should note that my working OLED is utilizing a UA panel, UA mainboard and a UB tcon Believe it or not since my original UA ton bit the dust.

There is no physical difference between the UA tcon and the UB tcon btw. It's all in the main board

[kevlar51]

Re: Just picked up a 55 inch LG 4k OLED for $50!

I should note that my working OLED is utilizing a UA panel, UA mainboard and a UB tcon Believe it or not since my original UA ton bit the dust.

There is no physical difference between the UA tcon and the UB tcon btw. It's all in the main board

Currently in my TV is a UA T-Con.

From my research, there are actually at least three UA T-Cons. I think there is one for each UA factory suffix (ie AUSYLJR, AUSZLJR, BUSYLJR). The one from AUSZLRJ is the same one that goes into the UB. I don't think they can all work in the UB model--but I could be completely wrong. The service manuals for both UA and UB are more or less silent on T-Con boards.

[kevlar51]

Re: Just picked up a 55 inch LG 4k OLED for $50!

to clarify--yes UA T-con and UA main board, all of which worked fine earlier today, but is currently essentially non-functional