LG OLED C7P55 - keep turning off after 15-30 seconds.

[M.Malone]

Sound and screen work while it is on.

I attempted to troubleshoot the power cable by unplugging it and pressing the power button for 10-30 seconds before trying to turn it on again. However, the problem persists.

I removed the back cover and tried replacing the power board, but the problem did not get fixed. Although, for a brief moment, it seemed like the issue was resolved as the TV stayed on for 5 minutes before reverting to turning off after 15-30 seconds.

I attempted to replace the T-CON board, but each time I turn the TV on with a new T-Con board, the whole screen appears cloudy dark spots (text still pops up, and has burned in images of a fox news channel), whereas when I reconnect the original T-CON board, the screen operates normal. The overall time the TV stays on before shutting down remains the same.

- I heard you need to downgrade the firmware to get different T-CON board to work, but is it even possible with TV only stays on for 30 seconds max?

There was an instance when the TV worked fine for half a day. I wiped down the 2 ribbon cables that connect the T-CON and main board, and it started working. Then it malfunctioned again, and I tried to wipe them again, but no luck.

I conducted several experiments to diagnose the problem with the TV:

1. Removing cables that connect the T-CON board to the Power board & Main Board (leaving only the Power board and main board connected) results in the TV staying on WITHOUT shutting off.

2. Removing cables that connect the T-CON board to the Main board (while the T-CON and Power board remain connected) also results in the TV staying on WITHOUT shutting off.

3. Removing cables that connect the T-CON board to the Power board (while the T-CON and Main Board remain connected) leads to the TV shutting off randomly.
(I attached the photos to make these more clear).

I'm unable to make an educated guess regarding the cause of the TV's problem. Initially, I thought it might be a power board issue, but it has turned into a lengthy project. Do you have any ideas about what could be causing this problem?

[Diah]

Re: LG OLED C7P55 - keep turning off after 15-30 seconds.

1- over all rs post i didn't notice or read you used digital meter to measure V. so do you own one !!!
2- from yours photos i can see the T-CON didn't screwed to chassis and this is wrong
3- you have 2 sockets on T-CON connect to power boards... one will be 12V and other 20-24V... let see which one are... use advanced option to upload photos over here
4- yours problem are on panel and SOS signal,, you need to disconnect only the socket of 20-24V between power boards and t-CON from T-CON side... this is enough the tv will remain on... a sgin are sound or the optic audio port lit red and remain red... at this step keep it on for awhile 5-10 minute... then as its on plug back the socket you disconnected , the screen will light on and if you are lucky it will remain on... give attention to the screen when you plug back the socket

[M.Malone]

Re: LG OLED C7P55 - keep turning off after 15-30 seconds.

1- over all rs post i didn't notice or read you used digital meter to measure V. so do you own one !!!
2- from yours photos i can see the T-CON didn't screwed to chassis and this is wrong
3- you have 2 sockets on T-CON connect to power boards... one will be 12V and other 20-24V... let see which one are... use advanced option to upload photos over here
4- yours problem are on panel and SOS signal,, you need to disconnect only the socket of 20-24V between power boards and t-CON from T-CON side... this is enough the tv will remain on... a sgin are sound or the optic audio port lit red and remain red... at this step keep it on for awhile 5-10 minute... then as its on plug back the socket you disconnected , the screen will light on and if you are lucky it will remain on... give attention to the screen when you plug back the socket

Hello, thank you for your reply. So, as you pointed out, I did, of course, screwed everything in. I used my voltmeter to check which one of the two wires is 24V and which one is 12V. I can confirm that the black wire is 24V while the white wire is 12V.

I waited for about 10 minutes with the TV on (with the 12V plugged in, not the 24V) before plugging in the 24V wire into the T-CON while the TV was still ON. The TV was in screen saver mode, but unfortunately, it turned off in about 30 seconds.

Is there anything I can do to remedy the problem? I just ordered a Service Remote for LG TV from Amazon, and it is supposed to arrive today.

[M.Malone]

Re: LG OLED C7P55 - keep turning off after 15-30 seconds.

So, I just received my LG service remote, and checked Power on/off status: the error message I get for every Power OFF is "POWER_OFF_BY_INV_ERROR(0x1E). I will attach the picture with this.

[EazyBone]

Re: LG OLED C7P55 - keep turning off after 15-30 seconds.

I am not well versed in OLEDs like diah is, so more take his advice but Inv error is on this service.manial and the fix-if you can call it a fix-as well. Maybe helpful? This is from C9 manual though I'm sure similar

Also my thoughts on if it's a power issue why would you change the tcon? I would think power supply and then main board first. But just asking as maybe I don't know something.

But I think the manual is saying the "module" and is referring to the panel. Maybe diah can answer

[Diah]

Re: LG OLED C7P55 - keep turning off after 15-30 seconds.

But I think the manual is saying the "module" and is referring to the panel. Maybe diah can answer

Yes you are correct, there are issue on OLED Cells which pulls high currents when they start ON. so the firmware section at the T-CON driver boards monitor this currents and when it exceed the T-CON will send SOS signal to Micom on the MB which it order the power boards to turn OFF.

So, I just received my LG service remote,

since you have S. RC. do the following

1- turn off the set complete from wall socket too
2- Gently with yours finger click on the screen surface corners and middle points., also you can try slowly to curve it from the side.. but don't do it in hard way to avoid the surface of Panel damaged.
3-disconnect the 24V socket only ,, and turn it on normally ... wait until you have the sign its ON ( as i described before )
4- send with yours S. RC IN_STOP one second later follow it with 0413 the TV will go to Stand BY... if it did mean it received IN-STOP correctly
plug it out from wall socket again... and do the point 2 again
5- after 5-10 minute from yours points 2 plug it in wall and tuen on.... wait enough time to have the set roll back the firmware and the Optic out put lit red...
now connect back the 24V socket and yours eyes on the screen..... hope it will remain on

[nomoresonys]

Re: LG OLED C7P55 - keep turning off after 15-30 seconds.

.

[EazyBone]

Re: LG OLED C7P55 - keep turning off after 15-30 seconds.

With how flaky oled tvs can be and how close the other tech is to same quality, I would skip oled if I was buying a new one.

Get 5 year warranty. I've got 2 oleds and I will say, I won't be going back to these "other" tvs lol. We will see though, I got a couple $6000 MSRP tvs I'm about to fix. Maybe I'll like them better

[nomoresonys]

Re: LG OLED C7P55 - keep turning off after 15-30 seconds.

For sure, not so worrisome with a good 5 year warranty, plus make sure you do use the warranty companies that are trusted, some are just scammers.

[nomoresonys]

Re: LG OLED C7P55 - keep turning off after 15-30 seconds.

They do produce a great picture, about the only knock is life expectancy is less and they're not as bright.

[M.Malone]

Re: LG OLED C7P55 - keep turning off after 15-30 seconds.

1- turn off the set complete from wall socket too
2- Gently with yours finger click on the screen surface corners and middle points., also you can try slowly to curve it from the side.. but don't do it in hard way to avoid the surface of Panel damaged.
3-disconnect the 24V socket only ,, and turn it on normally ... wait until you have the sign its ON ( as i described before )
4- send with yours S. RC IN_STOP one second later follow it with 0413 the TV will go to Stand BY... if it did mean it received IN-STOP correctly
plug it out from wall socket again... and do the point 2 again
5- after 5-10 minute from yours points 2 plug it in wall and tuen on.... wait enough time to have the set roll back the firmware and the Optic out put lit red...
now connect back the 24V socket and yours eyes on the screen..... hope it will remain on

Hello Diah, thank you for your reply and support throughout this process. I tried your method a couple of times today, but it hasn't worked its magic yet. The TV is still suffering from the same issue. I will continue to try out the method and monitor the results. Just to clarify, when you said "finger click on the screen surface," do you mean to tap on the screen or make a firm press on the screen? I did try both ways, but it hasn't shown any results, so maybe it isn't a difference maker.

I do want to mention this, though. On the day that I tried your FIRST method, and it seemed like it wasn't going to fix it, I posted the error message I found with S. RC. (POWER_OFF_BY_INV_ERROR), and about an hour or two later, the TV started working. It continued to work until this morning when it stopped working or regressed back to having the same issue after I had the brilliant/stupid idea to factory reset the TV. So, it hasn't worked since, nor after I tried your second method.

If there are any other ways that I can try to fix this TV, I am all ears. And again, I am appreciative of your support thus far.

P.S. I am not well-versed in TVs or any electronics, so this might sound foolish, but is there a way to bypass the SOS signal or anything like that?

[M.Malone]

Re: LG OLED C7P55 - keep turning off after 15-30 seconds.

I do want to mention this, though. On the day that I tried your FIRST method, and it seemed like it wasn't going to fix it, I posted the error message I found with S. RC. (POWER_OFF_BY_INV_ERROR), and about an hour or two later, the TV started working. It continued to work until this morning when it stopped working or regressed back to having the same issue after I had the brilliant/stupid idea to factory reset the TV. So, it hasn't worked since, nor after I tried your second method.

UPDATE: It just started working! I don't know how or why, but it began working. I turned it on and expected to quickly go through the initial setup process after the factory reset, but it continued to work. However, since this has happened a couple of times now, do you have any suggestions for preventing it from happening again or this issue resurfacing? My current firmware is 6.10.30. I heard there might be some firmware or something similar available for download on the LG website that can be updated on the TV; would that help prevent it? I'm not entirely sure if that's a viable option, but it came to mind as I write this. I don't think it's wise to factory reset again, as it seemed to trigger the issue the second time when the TV started working, but I'm willing to try it again if you have something else in mind. Thank you!

P.S. I will have this TV on till you write back HAHAHA

[Diah]

Re: LG OLED C7P55 - keep turning off after 15-30 seconds.

one time In_Stop enough to clear fault / error log and roll back firmware... but if there update via LG, connect yours TV to internet and let it pull update if its available..

but i do suggest to wait first... try use the TV as normal turn off and on next day... if it didnt make error.... then go to update... to avoid if it get fault during the update process and this fatal case as the MB will be dead

[M.Malone]

Re: LG OLED C7P55 - keep turning off after 15-30 seconds.

one time In_Stop enough to clear fault / error log and roll back firmware... but if there update via LG, connect yours TV to internet and let it pull update if its available..

but i do suggest to wait first... try use the TV as normal turn off and on next day... if it didnt make error.... then go to update... to avoid if it get fault during the update process and this fatal case as the MB will be dead

Hi, thank you for replying so soon.

I checked to see if LG has any updates for this TV through their menu (ABOUT TV). It looks like the firmware it is currently on is the latest version.

I will continue to use it as you advised. I will provide an update tomorrow or when the problem resurfaces again. But it looks like it is working for now! Thank you for everything.

[xnawani]

Re: LG OLED C7P55 - keep turning off after 15-30 seconds.

I'm having issues with my LG OLED G2 model. It has lines on the screen left side.. But thts not he main issue. The issue is the screen goes of every 30-40 seconds.. I had called the lg technician and he told me there is a problem with the panel thts wht is causing the screen to go off.. Is it true.. The error he got using is service report was BDP ERROR 7..

[xnawani]

Re: LG OLED C7P55 - keep turning off after 15-30 seconds.

@Diah pls can you help me here please..

[xnawani]

Re: LG OLED G2 - keep turning off after 30 seconds.

@Diah pls can you help me here please.

[Diah]

Re: LG OLED C7P55 - keep turning off after 15-30 seconds.

upload over here photo of yours screen behavior

[xnawani]

Re: LG OLED C7P55 - keep turning off after 15-30 seconds.

My screen is absolutely fine.. Apart from the screen lines which were there before. It just tht the screen goes off automatically.. I have to restart it again and again every 30_40 seconds.. Attached picture from the service remote.. Showing the error..

[Diah]

Re: LG OLED C7P55 - keep turning off after 15-30 seconds.

man its panel issue.... i asked i want to see the line when the TV On with signal