Thank you for that I needed this info to advise you correctly.
In this case you have a bad main board, these come in bad to me even all the time.
Also static electricity can hurt these boards really easily.
I will advise you how to do this safely.
Precautions must be used before handling these boards outside the TV's chassis.
I will bet you got a bad one so you need to return that one for an exchange.
Amazon is excellent with regards ***** ***** or exchanges;-)
I will stick with you until this is complete.
Please rate kindly thus far, it won't cost you anything to rate my service to you kindly,
Then you can reach me by simply replying to this message anytime.
Thank you and have a wonderful day!