No power

Andybiker

Just Joined
Dec 16, 2020
3
0
Hi all,
I have a cyclotrocity mid drive motor. I think it’s a bafang. With a c300s display.
I started having intermittent loss of power and flashing low battery on display. Then when turned off and back on was working again. This happened a few times on one ride. Now when I turn on it’s just flashing low battery on display with no power. I’ve tried reconnecting cables and tested the battery which seams good. Checked fuse on battery which is good but changed anyway.
Anyone have any idea what I can try.
 

sjpt

Esteemed Pedelecer
Jun 8, 2018
2,371
1,859
I'm afraid that could be a nearly dead battery. Even a nearly dead one will charge to the full amount (eg 42v for a 36v battery), and it is quite difficult to test how it behaves under load other by cycling with it.

Could also be something wrong in the controller, like a blown component. I'm afraid I can't tell you how to test that. You could look inside the controller for signs of damage.

Double check and triple check that the connections really are good. Also check for water in any of the electric parts/connections.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
12,982
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West Sx RH
Check the battery fully charged with a meter and also when it plays up, if the latter shows something like 24- 30v then a capacitor in the controller may be at fault.
 

pentiumofborg

Esteemed Pedelecer
Dec 13, 2020
1,383
374