Sounds like the cable that drives the window is broken, or has slipped out of the drive gear of the motor. You'll have to pull the doorpanel to see. If thats happened, or if anything else with the window assembly is broken, you can buy the whole assembly from a dealer for about $150. This has the motor, cable, and support brackets. All you have to do is bolt it in. Or, you can try a junkyard for the broken part......