I got very brave and identified the relevant fuse in the glove compartment fuse box. Nothing wrong with it. Bother! The rear window heater works OK, as does the rear window washer. The only things that don't work are the wiper and the window opening catch. Can anyone show me a picture of an X type estate with the back window open? I would like to see if I can open it manually if I can identify where the opening catch is.