Yes, it's probably just stuck. If the rear key switch works or you can get an assistant, try pushing down on the window by hand while the motor is engaged. This is the easiest and may get it moving. If not, pull the cover, take the cable off the motor and try connecting it to a cordless drill. You can also inspect - there may be a lot of rust in there. Once you figure it out, lube the parts and shoot some white grease down the drive cable before buttoning it all up.