Hi and
to the forum Naipe.
If it was purely a problem with the brake switch, the regenerative braking would have been activated, causing the wheel to be stiff to turn, but as you have already mentioned that there is no resistance, I think this is doubtful. Temporarily unplugging the two brake switch connections from the big four way block connector would prove whether the problem is being caused by the brake switches or not.
A failed Hall sensor inside the throttle assembly could cause a total loss of power, but it would not prevent the controller from being detected by your PC.
If a Reverse switch has been wired up and has been left turned on, this can prevent the controller from communicating successfully with the PC.
If it's an early MPIII, it might be a good idea to closely inspect the wires where they exit the motor to see if they have been damaged and are shorting against the edges of the slot in the axle. Cable damage is less likely to occur on the later versions with the modified axle.
If you cannot find anything obviously wrong with the wiring, I think you should email David
(wyh@goldenmotor.com) and explain your problem to him.
And please keep us informed of any developments.
Alan