Pedal assist sensor wiring, help requested

Old John

New Member
I have an 8fun electric bike conversion kit. In fact I have 2. One was installed no problem, the other is where I need help.
The issue is that there is no room for the pedal assist sensor on the crank side as its full of 3 gears.
I bought a left hand sensor but the wiring colours are different.
I want to rewire the plugs but don't want to blow anything up in the process so i'm looking for some help in wiring colours.
The 8fun kit has 3 wires coloured Brown, Yellow & black.
The left hand sensor also has 3 wires but they are coloured Red, Blue and Black, and within the plug are positioned differently.
I think and emphasize THINK, that the wiring is Red (&brown) are the power. Black is the earth and the Yellow (&blue) are the signal.
Can anyone either confirm this or correct me please?


Well-Known Member
I think you're right, but if you have a voltmeter, you could verify the power from the controller side.

On the PAS for a KT controller, power is 4.5 volt, while signal is 5.0V. Hence red/black is 4.5 and yellow/black is 5.0. Why is power lower than the signal? I believe there's a short circuit protection on power, which drops it .5 volt..

I bought a PAS sensor earlier this year from amazon, and it came blue, yellow, red. Yellow was ground. I had to test it on a bread board to figure that out,

Old John

New Member
Thanks for that Harry. I will check as you suggest. I have a feeling you could be right as if yellow is the earth, it would match up with the 2 pin locations.