PAS when I STOP pedaling, no PAS when I pedal!

steve2777

1 mW
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May 22, 2025
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Location
Cincinnati Ohio
I have a Hyper ebike that came with a 3 level PAS controller, and want to convert it to a 5 level. I purchased on Amazon a s866 controller and screen (sold as a set), and have removed the old one and installed the new. Most wire connections were straightforward and color coded, although I had to remove some connectors and install new ones or direct solder. On startup, the screen worked and the rear wheel rolled forward a few inches, suggesting the controller and motor were talking. I've set the screen parameters as I think they should be. (I did notice I can't access parameters p10 - p20; perhaps that's related to the other problem. ) But no pedal assist occurs when I turn the pedals. The new wiring diagram is enclosed. The linear brake, auxiliary power and boost signal connectors are unused. Photos of the original and new controller boxes are enclosed. The cable from the motor contained 5 small wires that color match to the hall line connector on the new box (but no white wire, which I've read is probably a temperature signal). Everything else is color to color, except the speed signal / PAS, and I've enclosed a photo of that connection. (That's my second try, after the blue and yellow didn't work either.) Are there any tests I can do with a multimeter, or other things to try? I'd hate at this point to have to abandon and re-install the old controller. Thanks!

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Does the new controller support PAS assistance? I read nothing about PAS in the wiring diagram? The white wire of the three pin connector is for the speedsensor.
Even it was the PAS connector, GND is wrong connected


https://electricbike.com/forum/forum/ask-lunacycle/ask-a-question/97507-pas-sensor-wiring-issue

You have swapped blue and yellow of the PAS connector....
But the controller expects a certain duty cycle in the PAS signal to detect forward pedaling. So maybe your PAS sends a wrong signal.

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As I mentioned, the photo was my second try with that connector, and I tried as you recommended first. However it's possible I tried that before I had set some of the controller parameters, so I'll try switching them back again to see what happens. Thanks.
 
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The PAS connector is labeled as "1:1 assistant" on similar controllers:

I guess your controller is for scooter use (no PAS, linear brake), not for bicycle use.
 
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I switched the blue and yellow wires. Now, when pedals are rotated, I still get no assist or MPH reading, but I get an error E-09 (controller). Is this telling me that the controller is defective? Do I understand you to be saying that maybe this controller doesn't support PAS assist at all? Enclosed is a picture from the Amazon listing that appears to show levels 1:5. If it's defective and I retirn it, do you have a recommendation of a different controller?Screenshot_20250522_150141_Amazon Shopping.jpg
 
The S866 really has a tacky feel on the buttons, but it's inexpensive, You can probably find it paired with a suitable controller on amazon, Here's a color version, 17A and you get a throttle which you don't have right now, olus a PAS sensor,


These S866 based units have a learning mode, you know, It wouldn't help with the unit you just bought, as it is for scooters. Hope you can return it.

For these low power bikes, a KT controller works quite well, I can't find any KT controller/display combos on amazon for less than 100 bucks though.
 
I just installed a new s866 controller on my ebike, and members were very helpful with some wiring problems, so now I have PAS. The problem is, it's only working when I STOP pedaling. When I pedal, the assist completely stops. Also, I can hear the motor running all the time when pedaling/ not receiving PAS, as if the motor was in "neutral". As soon as I stop pedaling, PAS kicks back in. Also, the 2 handbrake motor cutouts don't seem to do anything (though they still work the brake pads). The only way I can stop is to pedal, then turn off the controller at the screen while pedaling, and apply brakes. I'm baffled. Thanks!
 
Odd. I’d try disconnecting everything but the motor, battery, and display, then rerun the self learn function. If it continues to run full speed, then the controller is likely damaged.
Did the motor start spinning right away before or when you first connected the PAS unit for the first time?
Did you buy the controller and PAS unit together as a set, or separately. My guess is that the "boost signal" connector is for PAS, and "Speed Signal" is for throttle, but the controller may now be damaged.
 
Relearn didn't help. Esch time. motor spun as soon as unit was turned on. Controller and PAS purchased as a package so should be compatible. Everything I've read associates boost with a throttle. I may try connecting PAS to it tomorrow (Will have to rearrange the connector pins and assume that yellow connects to black). Could be controller is damaged and there's no way to make it work logically. This whole project was to get 5 PAS levels instead of 3 on the original controller, but I'm beginning to wonder if I should just live with 3.
 
Wasn't it established in another thread of yours that this controller is a scooter controller with no PAS input? If you connect a pas sensor to a throttle input, you will get funny things happening that aren't worth trying to explain, because you aren't supposed to be there.
 
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