Pedal Assist stops supporting / doesn't work properly

The pedal assistance of my e-bike only works sporadically / sometimes fails.

  1. Check all cable and plug connections including the Pedal Assist Sensor (PAS) and the motor cable for visual damages or tilts.
  2. Check the brake cut-off switches and cables. Possibly, the brake cut-off switches interrupt the motor support, as the sensor is located too far in the valve housing.
  3. To quickly check whether the brake cut-off switches are the cause of the assistance failure, you can disconnect both brake sensors by locating the two round connectors (3-pin Higo Plug, yellow) of the brakes in the wiring harness and plug them apart. The motor will now no longer be switched off when you brake while riding. Do a short test ride and check if the pedal assistance now works, then plug the brake cut-off switches back in. Also check that the starting aid works: Press and hold the minus button. After about 3 seconds the motor should accelerate to walking speed (ca. 6km/h). If this is not the case, the brake cut-off switch may interrupt the motor support.
  4. The sensor can be adjusted using the adjusting screw (2) at the cable input. First, loosen the grub screw (1) located at the bottom which fixes the adjustment screw.
  5. If the pedal assistance continues to fail, the control unit or the bottom bracket torque sensor may have to be replaced.

Wiring Harness Plug Assignment (UNI MK/Bobber/Swing):

Brake Sensor (disassembled):