Blubah
New member
Hello everyone,
Ebike is NCM Berlin 27,5 , Bafang rear geared hub motor, 36V 11Ah battery.
Is around 3 years old, no warranty.
Problem: during a ride, the motor stopped being powered. The display began to show , that battery is empty, although in reality its operational and almost full charge, 42V on contacts.
This seems to be common problem, but no solution or possible cause was posted on forums. That is the main issue.
After that, the display is difficult to turn on: instead of booting and staying on after press of the"on" button, the button has to be held, and if released the display switches off.
Hovewer, after couple of tries, removing battery, disconnecting display, it will turn on as when it was working normally, and will show correct battery voltage, and will power the motor. Only difference from "as new" state is , that holding the "on" button on display wont turn it off, when before it turned the display off. After turning it off by switch on battery, the problem reappears.
Video showing the issue:
At first, i show that everything works as expected. Then i turn it off, and i have trouble turning it back on. At around 5min20s in second video i get it to turn on and work properly.
My question to You is, is this a minor defect in controller, that could be fixed by resoldering bad component? Or is it the display, and controller is working correctly?
If you assume, that its not easily fixable, what do you recommend: a generic brushless controller+display, where i would need to solder the 9 pin plug ( doable for me), or a Bafang compatible, plug and play controller+ display( i assume, that all bafang hub controllers are compatible).
I am planning to buy such controller+display from Aliexpress. I could buy original , but controller only is 89 euro ( too much for me).
The battery connectors were cleaned, today the controller box was opened: nothing seemed burned , no visible water inside. Battery gives out 42V measured. PAS only, no throttle. One time before,~1 year ago battery showed as empty, although it was full. Contacts were wet. After cleaning battery showed full, motor worked, no issues. Before , other that this 1 time, no issues whatsoever with electronics.
Photo of controller , 2 stacked PCBs
![IMG_20241019_124537[1].jpg](https://ebikesforum.com/attachments/img_20241019_124537-1-jpg.16709/ "IMG_20241019_124537[1].jpg")
Photo of ebike in question
![IMG_20241019_193222[1].jpg](https://ebikesforum.com/attachments/img_20241019_193222-1-jpg.16710/ "IMG_20241019_193222[1].jpg")
Ebike is NCM Berlin 27,5 , Bafang rear geared hub motor, 36V 11Ah battery.
Is around 3 years old, no warranty.
Problem: during a ride, the motor stopped being powered. The display began to show , that battery is empty, although in reality its operational and almost full charge, 42V on contacts.
This seems to be common problem, but no solution or possible cause was posted on forums. That is the main issue.
After that, the display is difficult to turn on: instead of booting and staying on after press of the"on" button, the button has to be held, and if released the display switches off.
Hovewer, after couple of tries, removing battery, disconnecting display, it will turn on as when it was working normally, and will show correct battery voltage, and will power the motor. Only difference from "as new" state is , that holding the "on" button on display wont turn it off, when before it turned the display off. After turning it off by switch on battery, the problem reappears.
Video showing the issue:
At first, i show that everything works as expected. Then i turn it off, and i have trouble turning it back on. At around 5min20s in second video i get it to turn on and work properly.
My question to You is, is this a minor defect in controller, that could be fixed by resoldering bad component? Or is it the display, and controller is working correctly?
If you assume, that its not easily fixable, what do you recommend: a generic brushless controller+display, where i would need to solder the 9 pin plug ( doable for me), or a Bafang compatible, plug and play controller+ display( i assume, that all bafang hub controllers are compatible).
I am planning to buy such controller+display from Aliexpress. I could buy original , but controller only is 89 euro ( too much for me).
The battery connectors were cleaned, today the controller box was opened: nothing seemed burned , no visible water inside. Battery gives out 42V measured. PAS only, no throttle. One time before,~1 year ago battery showed as empty, although it was full. Contacts were wet. After cleaning battery showed full, motor worked, no issues. Before , other that this 1 time, no issues whatsoever with electronics.
Photo of controller , 2 stacked PCBs
Photo of ebike in question