If I want the screen to shut off when the lid is closed, will I need to find a way of making the "external" display power off?

I only have a 1 pixel vertical line in the screen, not sure if it's the cable or screen... That is with almost 99.9999% an LCD problem with a column-connection that has become unstuck. All along the top of the screen, the electronics from the backside PCB are connected to the liquid crystal layer. ...