1 LG OLED55C7P-U Turns off within 10 seconds...
Like the title says, I got an LG oled55c7p-u from a friend that turns off within 10 seconds of powering it on. While it's on for the first 7-8 seconds, the display and the image is perfectly fine. However after this mark, I see some artifacts appear on the bottom third of the screen, before the TV shuts off on its own.
I have already swapped out the TCON and Main board for other ones, and the issue persisted. I know that the next logical step is to replace the power supply board, but I can't see anything wrong with the power supply. I have reviewed the service manual for this TV, and I can't say it has been terribly helpful. Vx1 lock signal remains at 0V which is good per the manual.
I have an oscilloscope, and found that the DRV_ON signal is going low at the ~8 second mark just before the artifacts I mentioned appear on the display. When DRV_ON goes low, the 12 & 24V rails going to the TCON board also starts going low, as I would expect. Before DRV_ON goes low, I didn't see any issues on any of the power rails to cause DRV_ON to go low... I am tempted to force DRV_ON high and see what happens...
One thing I noticed, if I disconnect the 2 ribbon cables that connect the TCON board to the main board, the TV stays on (without a display of course) and I can hear sounds as I move the remote controller around. I am a bit stumped on this one, I am hoping you can help.
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@aeozyalcin what happens when you disconnect the ribbon cables from the T-con board to the panel (Driver boards)? Leave everything else connected.
oldturkey03 さんによる
Thank you for the quick reply! When any one of those 4 ribbons is disconnected, the TV turns off very quickly. I hear the relay turn on and off within a second, so I think TCON board knows it's missing a connection in that case.
aeozyalcin さんによる
@oldturkey03 an update: I also replaced the power supply, and the same issue persists.. I am pretty disappointed, I guess the fault is somewhere in the panel itself, but it's really weird that it works OK for about 10 seconds. Do you have any further troubleshooting recommendations?
aeozyalcin さんによる