LG 55EC9300 OLED half picture problems

[bjwhite]

Hello everyone. New member here posting because I have an LG 55EC9300 OLED that recently began to act up. I've done some searches here and the technical breadth of this group seems to be some of the best I've seen on forums anywhere (AVS, etc.) so I thought I would request some additional opinions.

This TV has worked fine for years but just two weekends ago we came back from a weekend trip to find that the TV's display only seems to half work. Overall, the operation of the TV is as normal--the TV turns on, can stream Netflix, the HDMI input works, the audio works, the menus work, the smart remote cursor works, etc. The only problem is that while the left side of the screen works perfectly, the right side right around the halfway point starts to fade out, and at 3/4s is actually dark. At this transition, there are horizontal lines as the picture fades away.

I have an extra T-Con board and an extra power supply board that have both been confirmed working--and replacing either board results in the same symptom. Considering everything else works fine, I'd be surprised if it was the Main board. But, since OLEDs are typical all working or not working at all, I'm surprised to see this "half-working" scenario.

Anyone have any insight or opinions? I've tried replacing the T-Con...same. I've tried replacing the power supply board...same. I've tried replacing both of them together...same. I've removed the ribbon cables to the T-Con side and wiped them...same. I've removed the ribbon cables from the panel and wiped them...same.

Any insight or opinions would be very welcomed. Thank you.

[bjwhite]

Re: LG 55EC9300 OLED half picture problems

Anyone? I'm curious if everything is ok my TV but the OLED display panel finally died.

[budwich]

Re: LG 55EC9300 OLED half picture problems

IF it were an LCD panel, I would say the drivers on the bad side are not being driven. That is a common display for such a failure. However, for a OLED, I am not sure that the same can be said. Having said that, in my reads, when ever an OLED has a panel problem, the system shuts down to prevent major issues. At this point, I would carefully check the bottom of the panel if there are edge driver boards to see if you can physically see an issue there in. Post a picture of that area in and around the edge board.

[bjwhite]

Re: LG 55EC9300 OLED half picture problems

Thank you Budwich. I am traveling tomorrow but will try to inspect closely and send any pics that might points us to the right direction.
I agree, it does seem weird that the screen isn't completely dark or that the TV hasn't gone into protection mode.

I actually watched it yesterday for about an hour as a test and it worked perfectly fine except the display--pictured just like the above. So strange. One other odd observation. When I turn the TV on and get the relay click from the power supply, after a second or so before the display fully turns on, it looks like the far right side of the screen gets lighter (like the grey backlight looking of a normal LCD TV on a black background) then goes away as the rest of the display turns on. I'm going to try and get this on video and post that. Could point us to the right direction.

[budwich]

Re: LG 55EC9300 OLED half picture problems

read thru this thread.
https://www.badcaps.net/forum/showth...ght=oled+score

His problem was a bit different in that he had shorts in the driver boards. Yours appear to opens / breaks somewhere. Hopefully, you can get it going.

[Diah]

Re: LG 55EC9300 OLED half picture problems

right side picture problem caused by Main Boards .. so LG trouble shooting said. use hair dryer to heat the MB the picture should change.
in case after heat no change send IN_STOP command to reset it

[bjwhite]

Re: LG 55EC9300 OLED half picture problems

Thanks everyone for the replies.
I removed the main board and went over it with a heat gun. Reinstalled it and there is no change to the symptom, it's exactly the same.

I will give it another try. Interesting about the IN_STOP suggestion. What will that do relative to the issue?

[Diah]

Re: LG 55EC9300 OLED half picture problems

Thanks everyone for the replies.
I removed the main board and went over it with a heat gun. Reinstalled it and there is no change to the symptom, it's exactly the same.

I will give it another try. Interesting about the IN_STOP suggestion. What will that do relative to the issue?

heating it with hair dryer should be done while the TV on and display picture...with heating the MB keep your eyes on the effected side if any change.. in case yes there change.. need to replace it

[bjwhite]

Re: LG 55EC9300 OLED half picture problems

heating it with hair dryer should be done while the TV on and display picture...with heating the MB keep your eyes on the effected side if any change.. in case yes there change.. need to replace it

Thanks for this clarification. I just finished heating the main board while the TV was on playing a netflix movie. No change at all during, or after.

Yeah, such a strange problem. TV works perfectly otherwise. So strange.


Here is a video:
https://youtu.be/TycrzCdtr7w

[budwich]

Re: LG 55EC9300 OLED half picture problems

:-( It is more likely that you have an open in the drive boards for the side that is dark. IF you are still trying to fix, you need to go down to the next level and start measuring voltages (labelled points on the tcon and edge boards) to see if there are obvious differences. As I mentioned, on OLED if a problem is detected, the system shutdown. However that "mode" usually is associated with shorts / over current draws. In your case, it is unlikely that's the problem as an "open" would result maybe in an "overvoltage" but problem not depending on the design of how the feed gets to the side. Further, you need to check the bottom edge board(s) especially at the corner of the panel. Also, does this panel have edge boards on each side? IF it does, then those are interconnected to the bottom edge board in some fashion... your problem may lie at the interconnection point. Just ideas, if you want to look further.

[Diah]

Re: LG 55EC9300 OLED half picture problems

Thanks for this clarification. I just finished heating the main board while the TV was on playing a netflix movie. No change at all during, or after.
Yeah, such a strange problem. TV works perfectly otherwise. So strange

:-( It is more likely that you have an open in the drive boards for the side that is dark.

+1

the open i guess i this case one of 2.

1- LVDS (the tow cable going out from Main Board to the T-CON driver Boards) need to inspect the end of them( burned / cutting PINs) under magnifier with rich light source. also inspect the 2 sockets on the main boards where they connected to.

2- signal source IC on Main boards.. just by replace boards with knowing good working one will approve. the cause in case points 1 was okay.

[bjwhite]

Re: LG 55EC9300 OLED half picture problems

Well I did spend a little more time on this. I changed around all of the ribbon cables between the T-con and the display...wiping down their connections before re-installing them. So the ribbon cable in position one is now position 3, position 2 is now position 1, etc.

No change at all.

What sucks is that a couple years ago I had an extra cable (the LVDS?) from the T-Con to the main board (I had a completely failed main board when I got the TV....) and those cables and main board sat around forever before I finally took them to electronics recycling. There is a section of that cable that "feels stiffer" than the rest of the cable. Makes me wonder about it for sure.

My next steps are to inspect the sockets on the main board and the ends of the LVDS cable as Diah suggests.

[bjwhite]

Re: LG 55EC9300 OLED half picture problems

Well....looks like I'm throwing in the towel. I ended up purchasing another fully working 55EC9300 and trying the ribbon cable and then the Main board from that TV and the screen was exactly the same. (Remember I had already tried a new T-Con and power supply board and swapping around the ribbon cables)

So looks like this is panel failure of some kind. Shame too....because the left side looks great! hah.. So I will be parting out this TV since all three boards are known good and working.

Thanks everyone for the suggestions and the help.