Magic Pie 3 Wiring

[Vroooom]

I noticed on port 3, when I measure the voltage using Battery + and Ground, my multi-meter detects a voltage that fluctuates between ~50 and ~100 mV. It will increase and decrease steadily. Ie, 50 mV, 60 mV, 70 mV... until it reaches around 100 mV and then begins decreasing.

When I measure the voltage using Lighting Feed and Ground I see 52 volts. I couldn't find any specifications that indicate what the Lighting Feed voltage should be. Anyone know?

I also measured the voltage between +5V and Ground; I see the expected 5 volts.

[Bikemad]

It looks like you have been using an earlier wiring diagram than the current one:



If I remember correctly, the Battery + and Lighting Feed were transposed to avoid the possibility of shorting together the Battery + and Ground wires in control harness if a brake or cruise/horn cable was inadvertently plugged into the throttle position and the switches operated.

The LED battery gauge on the earlier throttle may only work when the light switch is pressed in if it is fitted to a later type harness.

The voltage you measured at what you thought was the Battery + pin (which is actually the Lighting Feed pin) should have been 0V, as any voltage on this pin is only supplied by the lighting switch on the throttle, and this would have been unplugged while you were measuring the voltages. 

I couldn't find any specifications that indicate what the Lighting Feed voltage should be. Anyone know?

With the throttle plugged in and the light switch switched on, battery voltage is supplied to the Lighting Feed wire in the control harness.

Alan
 

[Vroooom]

TIL I shouldn't trust http://www.goldenmotor.ca/FAQ/questions.php?questionid=99 ; even though it is the first result when you google for Magic Pie 3 wiring diagram

[Vroooom]

@Bikemad - thank you for the detailed response.

[Wklatt]

That wiring diagram was very timely for me. I just received some "to be seen" lights for front and back, and was able to hook them up no problem. And until now, didn't realize the the grey button on the throttle was for turning on/off the lights. Works great.