Screen dark on one side

What I can tell you was my experience when this happened. A friend had the TV and she said it didn't work and was taking up space in her storage locker so I was going to haul it away and low and behold got it home and it worked for 6 months and then one day I turned it on and the left side had a black line through it. So some forum told me to tap it on the back lower right and it worked! Within a month it was 1/4 of the screen so I put it in a back room and forgot about it. A month or so later plugged it back in and it was perfect again. Well, I got another 6 months before I lost all picture and that was last week but I did research and it sounded like the Bravia is notorious for very expensive repair issues but twice I did get it to correct the problem with just shutting it off for a couple weeks or tapping the back. Not a great solution, so I hope you find a more permanant fix. maybe it's a fluke.