Also clean those connections. The following video APPLIES! Watch where they clean the connection.
It is possible it's the LCD but to figure it out you have to swap those cables out and do the work. Can be upsetting for those that want "only a guaranteed solution." Some LCD panels integrate the timing and control boards so that's expensive to replace.
That said, I caught the Amazon Prime Day Fire TV (by Toshiba) for a 50 inch Fire TV delivered to my door for $312.46. I wonder how much has been invested in repair on this set?
I have inherited an LG 47ls4500. The reason it was given to me was because it was replaced due to horizontal lines that flash in and out and appear to move down the screen. All three boards have been replaced in the t.v. I am wondering if replacing the cabling would do anything as that is a very cheap fix. If it is the LCD I would just assume trash it. Any thoughts are appreciated.