Hi Philip,
If the LEDs on the throttle have never lit up it sounds like you might have a 48V throttle unit which requires at least 30V just to light the first Red LED, but a 48V throttle would only affect the operation of battery gauge LEDs and not the throttle operation. Check that the throttle connector is still nice and dry inside, as water in the connector can cause problems.
I have just checked on my Magic Pie, and the blue LED on the Bluetooth dongle flashes once when the battery is first connected, and only lights up continually when my phone is actually connected to it via Bluetooth.
As the motor doesn't run and the bluetooth doesn't work, I would say it is either a fault in the battery supply cable and full battery voltage is not getting to the controller, or the controller itself may have failed.
You should be able to confirm that full battery voltage is reaching the controller by measuring the voltage between the Red lighting feed wire and Black or Blue ground wires with the switch on the throttle pressed in
(if they are easily accessible).
I would also recommend that you check that there is at least 4V between the Red +5V feed and Black ground wire going to the Pedelec sensor connector.
If you don't have a pedelec sensor connector fitted, make sure that the unused wires are not exposed and touching each other, as this could also prevent the motor from running.
However, if your Bluetooth was still working, a faulty Hall sensor
(in either the throttle unit or the motor) could also prevent the motor from running.
The MP5 controller does not beep like some of the earlier MPII controllers when a faults occur, but certain faults are displayed in the centre of the speedometer on the Bluetooth display
(and error codes are also indicated on the BAC-601 LCD display unit if fitted).
On the inside of the MP5 controller there is an LED indicator on the circuit board that will flash a different number of times to indicate different faults, but the controller needs to be removed to see this.
The reset function
(holding the brake and pressing the cruise button five times) only applies to some very early external GM controllers.
If you can't find an external problem with the wiring etc. then I suggest you contact your supplier and explain the problem and ask their permission to remove the controller so as not to invalidate the warranty.
At least you can rule out the brake switch and its wiring.
Alan