Good news. Whilst my car was in the garage and the hand brake set up was being done New hand brake cables, discs, pads and fixing kit. I asked me mechanic to check a couple of things whilst he had it all in bits and he discovered that the main nut that was holding the rear drive shaft on, had come lose (wow). So whilst it was moving around the sensor was not in line with the CV ring and was not reading it, and was always giving am intermittent problem. So all solved and no orange lights on the dash, cheap and cheerful. Thanks for the advice. Paul