Thanks for all your advice. I will try it all. Someone said that it can be the rear ABS unit/sensor but that seems to work. Very odd. Personally I think it is a loose connection of sorts. It stopped working, then started after electrician did some cleaning. Worked coming home then the next day again nothing. I am sure he will sort it but most places closed so can only try again next week.
There was a useful two-page tech explanation of the ECU in December's Bike magazine. Made it sound quite straightforward, in principle.
Dunno how I missed this one. Went up there once on a site survey when I was living in RSA and had some future in-laws living in Walvis Bay for a year or two. Pretty epic country. Be sure and drop some pictures of those rides.
