LG OLED 55EG9100 TCON troubles

[jfl2507]

So I've been having trouble with this TV for years. The symptom was every now and again the image would just freeze and sound would keep playing, a quick power down and power up would fix this until the next freeze. The problem went like this until it started displaying green lines and artifacts as well, also it would not even turn on until it was warmed up. I originally thought it was the main board so after ordering a new replacement it did not fix the issue. Next on the list was a TCON board, I could not find a new one at all, so I bought one that was compatible with my TV used, not exactly the same but description said it worked with my 55EG9100. When I installed it the TV would turn on again. But there were burned in images of a fox news channel and cloudy dark spots, colors way off. I thought I got a defective TCON so I ordered again another one this time matching the exact model my TV came with. Same results, though this time it had a different channel logo lol , the original still works and no burned images but it takes a bunch of tries and i have to warm up the TV for it to get an image.

I've done a lot of reading and it does look like somehow my original TCON board has some settings that need to be transferred to the replacement, it looks like an expensive solution for that Jig interface. My question is if the settings are stored in an EEPROM chip I can desolder from one board and put it on the one I bought on Ebay? I am handy with electronics and can deal with most surface mounted components except re-balling a video chip lol

I have some tools if someone can guide me in the right direction, basic multimeter, hot air station & soldering iron, Digital Oscilloscope. I am including a picture of the 2 TCON boards I bought top one is not exact match but compatible, bottom one is exactly like the original both work but give different screen artifacts. There is an 8-leg EEPROM chip on the left side corner if its as simple as swapping it from the original or is it more complicated than this? If there are any schematics for this TCON board out there that would be extremely useful

[lotas]

Re: LG OLED 55EG9100 TCON troubles

But the firmware is most likely in flash and eeprom.

[Davi.p]

Re: LG OLED 55EG9100 TCON troubles

Well, watching some Oled tcon it seems them are different from lcd ones, not all, the p.supply part is much similar, the signal part not much, them have a real processor when in lcd not, so i would have expected an optional serial port for debug but i don't see any. Also the TP near the flash doesn't seem them are for an emmc but maybe a Nand or OneNand.. so flying wire connection is not an option maybe.. the only option that it could be for me is to deeply dive into service menu trying to find a download option to save customization data for tcon to an usb flash pen.. it surely needs a service remote or app.

About original one, does it happens that defects shows at absolutely cold board?
If you want to fix it i have a test for you maybe..

[William1967]

Re: LG OLED 55EG9100 TCON troubles

With older models the NAND and Eeprom software must be taken from the old defective t-con and uploaded into the new t-con. The NAND software for example is used for the mura clouding , see attached picture.
Newer t-con only need the NAND software.

[jfl2507]

Re: LG OLED 55EG9100 TCON troubles

Thanks for the input so far guys, To answer Davi, Original Board was working for 2 years with no issues other than an occasional freeze up a couple times a week. When board is completely cold it acts like a dead TCON, power supply clicks red light on bottom but completely black screen. Powering on and off for several minutes will eventually bring the screen though now random green lines and pixels will show up. The replacement boards work right off the bat, but a lot of MURA issues. I am thinking of biting the bullet and re-ball the flash chip. Its a BGA 63 chip so I am looking for a stencil with an 0.8mm pitch, I have a cheap BGA station I can use but will have to practice on lifting ram chips from old video cards to get comfortable with it haha. I do remember the voltage of Q21 was 3.5V when it was working and dropped to zero when it wasn't working but this was me fiddling with the meter at components near the power supply connector.

A closer look reveal pads next to both EEPROM and flash chip, pads labeled for reading, writing, write protect ect. So if there is such a thing as a simple Arduino EEPROM programmer that can be attached to these pads though not sure about the flash chip lol.

[Davi.p]

Re: LG OLED 55EG9100 TCON troubles

My question: how much you have used the replacement tcon boards? I'm not so sure the original one is defective, i'm guessing the fault could be both msin boards.. them are a tipical defect of LG..

[Andrei_UK]

Re: LG OLED 55EG9100 TCON troubles

But the firmware is most likely in flash and eeprom.

Hi

Do you have Idea how can I doo that to write to the new T-CON ( OLED55 C9 )
The original T-CON it's definitely foult ( turn on TV all good but acter 30 sec power off )
New T-con all works good exept with vertical bands which you can notice when gry pic ( like in your pic )

Thank you

[Andrei_UK]

Re: LG OLED 55EG9100 TCON troubles

With older models the NAND and Eeprom software must be taken from the old defective t-con and uploaded into the new t-con. The NAND software for example is used for the mura clouding , see attached picture.
Newer t-con only need the NAND software.

Hi

Do you have Idea how can I doo that to write to the new T-CON ( OLED55 C9 )
The original T-CON it's definitely faulty ( turn on TV all good but after 30 sec power off )
New T-con all works good exept with vertical bands which you can notice when gry pic ( like in your pic )

Thank you

[dskall]

Re: LG OLED 55EG9100 TCON troubles

Have you tried reflowing main chip?

[Andrei_UK]

Re: LG OLED 55EG9100 TCON troubles

Have you tried reflowing main chip?

No I didn't, you mean the big platinum chip ?

[Diah]

Re: LG OLED 55EG9100 TCON troubles

No I didn't, you mean the big platinum chip ?

dont play with chips.
search after apache server to downgrade or roll up fimware on LG OS TV. here in this forum i wrote about it too.

if you downgrade or rolled up the firmware... it will match yours replament T-CON firmware part with the main firmware.. also if you send command IN_STOP it will match them and send refresh to t-con to remove any burn caued by T-CON

[Andrei_UK]

Re: LG OLED 55EG9100 TCON troubles

dont play with chips.
search after apache server to downgrade or roll up fimware on LG OS TV. here in this forum i wrote about it too.

if you downgrade or rolled up the firmware... it will match yours replament T-CON firmware part with the main firmware.. also if you send command IN_STOP it will match them and send refresh to t-con to remove any burn caued by T-CON

Hi

Thank you for your suggestions, I will try find how to downgrade the firmware maybe a last solution, in this stage I have done IN-STOP few times and the WebOS apparently looks like factory reset , but still I got the vertical bands slightly vizibile

One question, it's the T-CON has eeprom chip? I Was thinking if I read/save the data from the old T-con and the writing to the new one .

Thank you again for any suggestions

[Diah]

Re: LG OLED 55EG9100 TCON troubles

Hi

Thank you for your suggestions, I will try find how to downgrade the firmware maybe a last solution, in this stage I have done IN-STOP few times and the WebOS apparently looks like factory reset , but still I got the vertical bands slightly vizibile

One question, it's the T-CON has eeprom chip? I Was thinking if I read/save the data from the old T-con and the writing to the new one .

Thank you again for any suggestions

yes you can

[dskall]

Re: LG OLED 55EG9100 TCON troubles

No I didn’t, you mean the big platinum chip ?

The chip on original t-con. Ok I'm replying to OP. Didn't see the change in posters to this thread.

[Andrei_UK]

Re: LG OLED 55EG9100 TCON troubles

The chip on original t-con.

No I didn't, I will try the option by rolling back or downgrade if posible if not I waiting for the eeprom flash usb and try to read the 8pins chip from the t-con ( hopefully it's the eeprom chip one )

[lotas]

Re: LG OLED 55EG9100 TCON troubles

No I didn’t, I will try the option by rolling back or downgrade if posible if not I waiting for the eeprom flash usb and try to read the 8pins chip from the t-con ( hopefully it’s the eeprom chip one )

432FK = 24C32 (TSSOP8) - 1.7 V to 5.5 V EEPROM

F59D1G81A - 1 Gbit (128M x 8/ 64M x 16) 1.8V NAND Flash Memory

[Diah]

Re: LG OLED 55EG9100 TCON troubles

432FK = 24C32 (TSSOP8) - 1.7 V to 5.5 V EEPROM

F59D1G81A - 1 Gbit (128M x 8/ 64M x 16) 1.8V NAND Flash Memory

this is no need at all... we do know the firmware of the LG contain NFC.bin part where it will saved at T-CON eeprom.

the other parts of the firmware will be saved at mainboard eeprom and micon. micon communicated with T-CON eeprom.. if there grab between micon and T-CON eeprom version will cause this burn.. we had always successful story when downgrade or rolling up the firmware on PC Apache server... so all firmware parts will match. no soldering nothing hardware work. easy way log in EZ adjust service menu or at IN_Start we will find all version we talking about and also the ability to see when & how many there pixel refresh has being done.

[Andrei_UK]

Re: LG OLED 55EG9100 TCON troubles

this is no need at all... we do know the firmware of the LG contain NFC.bin part where it will saved at T-CON eeprom.

the other parts of the firmware will be saved at mainboard eeprom and micon. micon communicated with T-CON eeprom.. if there grab between micon and T-CON eeprom version will cause this burn.. we had always successful story when downgrade or rolling up the firmware on PC Apache server... so all firmware parts will match. no soldering nothing hardware work. easy way log in EZ adjust service menu or at IN_Start we will find all version we talking about and also the ability to see when & how many there pixel refresh has being done.

I think you got right about the version on the IN-START , I maybe mistake but I can see two versions at the OLED info different number between panel and new t-con I will update tomorrow the version of dose two , I will try to find how to post some pictures here ( I m new on the account) you guys to see about the vertical bands and some info from IN-START

[Andrei_UK]

Re: LG OLED 55EG9100 TCON troubles

I think you got right about the version on the IN-START , I maybe mistake but I can see two versions at the OLED info different number between panel and new t-con I will update tomorrow the version of dose two , I will try to find how to post some pictures here ( I m new on the account) you guys to see about the vertical bands and some info from IN-START

Some pic attached

[Diah]

Re: LG OLED 55EG9100 TCON troubles

Some pic attached

can you show us here same page IN_START of the original T-CON in place ?

did you sent IN_STOP before while original T-CON in place ?