Facing TV Problems? Ask a TV Technician.
It could be the ribbon cable...but it's worth trying the bottom left buffer.
If the ribbon on the panel is at fault, then you need the panel -
There are 3 model variations on your TV, if you choose to go with the panel, you have to get the extra letters at the end of your model number -
then put PDP in the search box for price and availability.
That would indicate the panel is good. But the ribbon is fused onto the panel, and if it's cracked it could cause intermittent bars. If you want to test that, fire up the TV, use a helper to watch it, then go to the back of the TV and stroke those ribbon cables just below where the bars show up. I use a toothpick to stroke the cables and apply light pressure to deflect the cables, or move them. The picture should be good if they're ok.