Motor & Controller Faults
If the motor loses power, jerks, makes a new noise or shows an error, start here. You do not need to measure voltage or open electrical parts.
First checks
- Stop riding and turn off the bike. If the bike is hot after riding, let it cool naturally.
- Check the battery level. Let a hot battery cool before charging with its original charger.
- With power off and the charger unplugged from the wall, check that the battery is properly seated. Look at accessible cables for obvious damage or loose plugs. Do not pull wires or open covers.
- Photograph any error code. Note whether the problem starts immediately, on hills or after a longer ride.
- If power cuts out again, the bike jerks or there is damage, contact support before riding again or buying parts.
What the codes mean
| Code | Plain-language meaning | Next step |
|---|---|---|
| E07 | A problem related to the motor or its connections | Follow the E07 guide or contact support. The code alone does not mean the motor needs replacing. |
| E09 | A problem reported by the controller, the unit managing motor power | Let the bike cool if hot and contact support if it remains or returns. |
| E12 | The bike cannot communicate correctly with the battery's protection electronics, called the BMS | Check that the battery is seated properly with power off, then contact support if it remains. |
See Display & Error Codes for the full list. Codes and equipment can differ by model.
New noises or motor running without movement
Stop riding if you hear grinding or knocking, feel a wheel catching, or the motor runs without driving the bike. With power off, look for an obviously loose or damaged chain. Keep fingers away from chains and sprockets. Follow the model's care instructions for routine chain lubrication; ask a repairer about adjustment or replacement.
Send support a short video recorded safely while stationary. Do not ride to reproduce a fault for a video. See Drive & Transmission.
Repairs and electrical tests
Voltage measurements, wiring tests, controller settings and motor removal are for a qualified repairer following the correct model instructions. Do not change current or voltage protection settings to clear an error.
Repair videos are available in Technical Guides. Contact support before dismantling parts for a warranty claim.
Warranty: The controller carries a 12-month warranty. A warranty claim requires the fault to be a performance failure or quality problem attributable to the product that cannot be repaired. See Warranty Claims.
Warranty notice: Motor warranty is void where the coil is burned, or where the fault results from demagnetization, short circuit, open circuit, abnormal noise, material damage, deformation or fracture caused by external factors. Unauthorized disassembly voids coverage. See Warranty.
Motor warranty period
The motor carries a 12-month warranty on the D-series, covering performance failure or quality problems attributable to the product that cannot be repaired.