Further to this problem, I have thought about it again. The divertor is in the off or normal position when it pumps out to drain. To recirculate the water, power is applied to the wax motor solenoid which heats up, expands & pushes valve over to divert side. When power is removed from solenoid then wax cools (3 min) then moves back to drain position. Therefor in diagnostic mode pump test there should be no power from the controller to the solenoid. Maybe you could test that with a meter.
Lincoln Appliance NZ, March 2011