I'm relatively new here and I think this may be my first post. I've attempted to search for some advice on the problem I'm about to tell you about but couldn't find anything quite the same (lots about regulators and plastic bits breaking though!).
A common problem on Scenics, possibly a fault in the wiring at the door frame or connecters.
Have a read through the link below it might be of help
Renault Scenic II - Drivers Window