• Howdy! we're looking for donations to finish custom knowledgebase software for this forum. Please see our Funding drive thread

Bafang Error 21

chashb

100 mW
Joined
Jan 22, 2007
Messages
36
I recently received my Tripod velomobile from Columbia Cycle Works. Something has gone wrong in that I get an error 21 when I try to ride it. This is a speedometer error. Sure enough, my speedometer stays at 0 mph now all of a sudden. The Bafang controller won't run with any error messages, so I'm dead in the water...

Out of the Bafang controller there's a three conductor cable. There's a red, black, and a white wire. I believe that the red wire is the positive bias supply for the sensor, the black wire is the return, and the white wire is the output of the speedometer hall sensor. Is this correct? I'm getting no voltage between the red and the black wire but am getting 5V between the white and the black wire. I suspect that this is because the sensor input to the Bafang controller has a pull-up resistor. This also suggests that the 5V sensor supply in the Bafang controller is still working. I'm thinking that perhaps the red wire is open somewhere in the cable between the Bafang controller in the front of the velomobile and the back end where the sensor is mounted to the rear wheel dropout. Does this sound right? If any of you have a functioning Bafang controller, I'd greatly appreciate it if you could check and see if you're getting a voltage between your red and black wire coming out of the controller. Is it easy to get inside the Bafang controller should I have to re-establish a connection at that point?

Thanks!

Charlie
 
Back
Top