Thanks elekie-doc, the single pump does indeed do both. I eventually found a video of how to dismantle the steering column switch - which fortunately we didn't attempt as it didn't solve the video maker's problem. The next, and most obvious diagnosis in our case, was a seized pump; presumably a not uncommon occurrence in cars which stand idle much of the time. The video went on to show how to access the pump behind the front wheel arch cover and dismantle it. It was indeed seized; filled with rusty gunk. It just needed a good clean and it now works perfectly......and I feel slightly less indebted to our non-mechanical host as I guess the local garage would have just replaced it with a new one. A good example of 'if you don't use it you'll lose it'.