Judging from the faults , this is a common fault in a lot of LCD TV Panels.
The actual issue belongs to what is called a T-Con Board which should be located centre top underneath a metal shield.
If you follow either the ribbon cable or a bunch of cables going up to the top middle ( From the tuner and audio pcb ) , then that's where the board is.
They can be cheap to replace, since this acts as a buffer between the LCD Panel itself and the Mainboard.
You remove this shield and it will have 2 ribbon cable connectors attached to the top of it. You have to make sure you get the same identical board from the model number, which should be on a white sticker or the board itself.
Hope this helps.