55" LG LED HDTV picture issues

I have a LG 55 LEd hdtv that is just over one year old. The sound is perfect, but my screen went to left side is light grey with black vertical lines, the right side is a darker grey. When I turn it on now I can see half of the LG logo and the sound is there but nothing on the picture. I replaced the inverter board with a brand new one and no difference. My question is, do I need to replace the main control board, or is the screen dead. Can't find any tv repair shows open on weekends and trying to repair this myself. The tv is a 55le5400-uc

Here turbo3, did they have to do any reprogramming? Or did they just plug in the new board and thats it?

Well, I replaced the main board and turned the tv on. The left side of the screen has have of the lg logo, the right side is just light grey. I got the menu to come up for a second, but that was just on the left side, and it was flickering the whole time. then nothing. Anybody have any ideas.
thanks!!