BBS02 750W Bafang throttle stopped working

[chashb]

At the Bafang harness side of the throttle input going to the motor, I still read +5V between the two lower pins adjacent to the notch on the female connector. This tells me the +5V bias supply from the controller to the hall effect throttle isn't blown. When I disconnect the throttle cable and power the hall effect throttle with a separate +5V supply and look at the signal output, I see from 1.1V to ~4.2V as I turn the throttle from home to full throttle. This is what I'd expect... I even tried shorting +5V to the throttle signal directly on the harness side of the throttle input going to the motor to force a full throttle condition and still nothing happens.

Has anyone else ever had a case where the throttle designated assist flash setting became corrupted to '0'? It's the only thing left I can think of that would cause the throttle not to work anymore?

BTW, I'm using the EMPowered .el file btw... Everything worked fine when I first downloaded the file to the Bafang controller...

Thanks to anyone who can provide some input!

Charlie

 

[chashb]

I connected to my laptop computer and read back the parameters stored in the controller using the Bafang software. The throttle settings were not corrupted. This is actually a good thing! But... The mystery continues as to why the throttle won't work....

 

[fechter]

It would be nice to measure the throttle voltage at the controller, but the potting makes this a pain.

An easy test, measure resistance from the throttle signal pin going to the controller against battery negative. Power off. You should see something like 20k ohms. Not zero and not infinite. This way you can tell if the throttle wire is broken or shorted.

 

[chashb]

Thanks Fetcher! It's been a long time! Hope the e-bike world has been kind to you!

I stumbled onto the old lesson that assumption is the mother of all %#$@ ups.... lol The velomobile had an unusually long throttle cable that was spliced 3 times along its length between the throttle and the male throttle connector of the Bafang harness. I assumed that when the throttle stopped working, the problem developed in the multiply spliced section(s) of the cable. The splices weren't done especially well which supported that assumption... I utilized the Bafang male end of the original cable (about 4") and spliced that directly to the throttle wires. From there, I purchased a 40" length of throttle extension cable from Lunacycles to complete the throttle run in a much neater way than the original. It turns out that the problem was in the 4" 'factory' cable that I spliced to the throttle! The throttle signal line was open... I should have checked it before splicing it in, but I was certain the problem wasn't there... lol This is was what led me through the weeds as I was starting to assume that the issue was in either the main Bafang harness or the controller itself after several checks with my meter.... I'm back in business now!

Thanks again!

Charlie