Question LG 65EF9500 screen half black, other half alternating solid colors

[MichaelLG]

Hello,
I've been searching for a few days now and can't seem to narrow down my issue so thought I'd post here.
I have had this TV for about two years with absolutely no issues.
I came home from a trip to find my tv on (was off when I left) and half the screen was black while the other half alternated between a solid blue, purple, green, and white. The remote does not work except to turn the tv on or off (yes, I replaced the batteries). I also the joystick on the bottom of the tv and it also had no effect.
I called LG and they referred me to a local rep for repair. Some how, in the entire Seattle metro area, there is only one rep and the reviews are quite poor. I am would be fine with replacing t-conn board or other parts myself but have no idea how to troubleshoot and determine which part may be faulty. I was hoping that the screen cycling through the colors and the remote not working would indicate a specific issue but have not been able to find anything online to support that.
Appreciate the input.

 

[helpstar]

Did you unplug the TV yet? While off, push the power on "joystick", till the power led wents off. Wait for another 2minutes before plugging it in again.

Were other electronic devices as well? Like radio clocks,....
Was a thunderstorm in your area at this time?

 

[MichaelLG]

Hello,

Thanks for the reply.
I did unplug the TV but didn't know anything about trying the joystick.
No other devices had issues. I was out of town for several days so perhaps that is a possibility.

I ended up replacing the mainboard and the TV does work now. Unfortunately, even though I bought what appears to be the exact same board, the software appears to be a different version. I also have to reregister my remote every time I turn it on.