Master switch - The main reasons for the master window switch to stop working are dirt, dust, spilt drinks, cigarette ash etc, which fall in past the switch buttons and contaminate the internal electrical contacts. Once the contacts become dirty, current draw is increased through the switch, which in turn fatigues and snaps the internal springs of the switch, and the switch no longer works. These switches are not serviceable. If you do get a new one, make sure you keep it clean.
Executive and Berlina RH Master window switch - Part Number 92034557
Executive and Berlina LH Master window switch - Part Number 92034558
Executive and Berlina Rear window switch - Part Number 92045551BA
Power window module - VN's with electric windows have a module just below the steering column, which is responsible for power window master control. The module contains a circuit board, and these boards suffer from dry solder joints. Solder is directly affected by variations in temperature, and can start to show signs of fatigue on hot days, by stopping window operation as the solder joint expands and separates. Eventually the module will fail totally, and the windows will be inoperable. A replacement module is usually required.
Electric Window module - Part number 92034559
Power window circuit breaker - The power window assembly is protected by a circuit breaker in the under dash fuse panel, which is basically a fuse that disconnects power flow when excessive heat and/or load is present. Like anything electrical, these circuit breakers can fail and the power windows will not work.
Circuit Breaker - Part number 92035956
Window wind-up - The front windup windows of VN's and the like, use many rubbers to seal against water. These rubbers move, either up or down, and can restrict the operation or ease of movement of the windows. These rubbers are available new, and when installed, they should be glued in place.
RH Front rubber - Part Number 92047144 (rear edge of glass)
RH Front rubber - Part Number 92046805 (front edge of glass)
LH Front rubber - Part Number 92046429 (rear edge of glass)
LH Front rubber - Part Number 92046805 (front edge of glass)