|Double check the connection to the screen. Remove and then refit firmly. It is also just possible that the connection at the other end (motherboard) was a bit loose and fitting the screen disturbed it, so if necessary refit that one too.|
One other (less likely) possibility is that the cable as failed where it hinges. If anything appears on the screen what you lower the lid then that will be the reason.
Always pop back and let us know the outcome - thanks