As well as the main fuse I would check this:
I put a full set of lecky windows in my 5 door when I was doing an engine conversion. I took all of the motors apart, checked and greased them before installing because I had heard they get crusty like this inside. One of them didn’t work so thought the motor was up the creek, I took it apart and magnets looked good and there was no play etc so wasn't convinced it was a gonner (it's a right hassle to put back together though!). I looked to see how much replacements are and thought chuff that, took it to a local old school HiFi repair man and he found that the resistor on the motor had burnt out, £5 later a new resistor had been soldered on and was as good as new!
