[Stephen Edwin]

I reckon to always check simplest cheapest things first. Check connections and the switch. This does mean stripping out the door trim. That's a reasonably straightforward job on my J reg 200SE.

Whilst the door trim is off, has water got inside the door? That could cause an "after winter" electrical problem? There's a sheet of polythene that should be in strategic place behind the trim to deflect water from the window down out of harm's way.

Good luck.