Thanks RusselW. I am not used to harness diagrams but I see no commenality with the handbrake circuit. We had thought that the
ABS control might be the problem, but Bosch no longer supply any replacement and when they did they were in thousands of dollars!
The coolant level light has been a problem in the past, illuminating when all seemed well. Recently the traction contol has seemingly turned off of its own accord on one occasion.