But lightning strike? No shop I know would take that in. The problems could be every board and even the LCD. I have friends in such shops and they know to never accept such.
If you feel otherwise, replace the board you think it is or use my old wise tech's advice which is "when you're not sure, replace the cheapest part or board first."
I watched a tube video to trouble shoot this TV and found that there is no back light until I pull the wire from the power board off the main board. When the wire is disconnected the back lights come on. Would this indicate that the main board is bad or the power board is bad. There are no obvious burnt spots or swollen diodes or resistors. This TV was on in a room where the tree outside the room was hit with lightening. It fried the DVR, (belonged to the cable company) then I couldn't use the HDMI connections. But it worked through the coaxes fitting for 2 months. Then recently I went to turn it on and it wouldn't come on. What do you think I should replace?