pas sensor works backwards.


New Member
I have been using my throttle for my ebike but decided I wanted to try the pas sonsor. I connected it and now when I pedal backwards it works but not forward. My bottom bracket would only accept the pas on the sprocket side otherwise I would just take it apart and put it on the otherside. can I change the wiring so it will change the direction of pas?
Flip the plastic PAS disc around. I did this on a kit installation and experienced the same result as you. Keep it on the chain ring side, just flip it over.
There should be arrows on the sensor disc pointing toward the direction of travel. If flipping it doesn't work, you will have to get a different sensor.
I had the same issue and I caused it cause I disconnected the metal bracket from the sensor as it was getting rusted.

After I cleaned the bracket and reinstalled I must have flipped it. Anywho the attached video helped me resolve it.

Or you can swap the positive and negative pins in the connector. Flipping the wheel is the easiest. One bike was bucking. Someone played a joke and reversed half of the magnets. It is weird pedaling backwards and going full speed ahead.
Or maybe you don't need to don't swap anything. KT controllers have both forward and reverse configs in their settings for this exact reason. You go into the settings in the display and look for the PAS sensor settings. Use that to reverse the direction. Easy-peasy.

Flipping the sensor around is what I think everyone is thinking of flipping if talking about flipping hardware; not flipping the disk. A PAS disk just has magnets in it and those don't change anything if you flip the dis around except they work better on the proper side where more magnet is exposed. On a couple of my bikes I have flipped the sensor around, but only because it let me physically move the sensor closer to the PAS magnet. Here's a pic of one. See how the metal bracket is an outie, now? Thats what I needed to get the sensor close to the disk. Also see the little screw that mounts the sensor? I unscrewed the sensor, put it on the other side of the bracket and poof it works on the forward setting but is traveling in 'reverse'

Thanks for the guidance, however on my Voilamart I only have PAS 3 or 5 level setting on the SW900. Unless I’m missing something.
Thanks for the guidance, however on my Voilamart I only have PAS 3 or 5 level setting on the SW900. Unless I’m missing something.
Okay, That means that there is a fault with likely the display or the controller. The display is the less expensive of the two, so replace that first to see it that is the solution.
I just watched that video. He basically did the same thing I did but the different mounting of that particular sensor let him reverse it and keep it on the same side.

Since the OP posted in 2017 and @ezrider_028 fixed his problem, I suspect this thread can climb into its coffin and go back to sleep.