I have an LG 49UH850V that has gotten this wierd glitch that toggles on/off with a period of approx 2-3 sec as shown in the attached images.
I've disassembled it and checked that the link cable between the motherboard and panel is connected and all the other cables. Nothing pops out as something that could be an obvious cause.
The motherboard has a slight humm that changes in frequency while the glitch is there.
I suspect either an IC has bad soldering on the main board as it gets quite warm or some sort of power supply issue. But am looking for some feedback or ideas of what to do/where to look for debugging...? Any suggestions is welcome!
And the service manual is https://elektrotanya.com/lg_49ub850v-za_chassis_ld41v_mfl68084505_1403-rev00.pdf/download.html