E4 Error CodeUpdated 4 hours ago
Description
E4 appears on the display and the scooter may lose power, stutter, or refuse to engage the motor(s).
Example: The scooter shows E4 during acceleration or after a bump and the motor cuts out.
Symptoms
- E4 error code on the display (intermittent or constant).
- Jerky acceleration, no throttle response, or sudden motor cut-out.
- Error appears after a bump/pothole, hard acceleration, or during power-on self-check.
- Possible grinding, scraping, or electrical buzzing just before the error.
- One wheel spins while the other doesn’t, or both do not engage.
Causes
- Loose or damaged motor phase wires or hall sensor connectors.
- Pinched, frayed, or water-damaged motor cable at the axle or where it enters the deck.
- Failed hall sensor in the motor or corroded hall connector.
- Faulty controller output on one motor channel.
- Battery/BMS sag or connection issue triggering controller protection under load.
Solution
Most E4 cases are caused by connection faults on the motor wiring or a failing hall sensor.
Try the following, in order:
- Inspect motor cables on both sides; reseat phase and hall connectors securely.
- Correct any pinched or abraded cable sections; provide strain relief; avoid riding until repaired.
- Swap left/right motor connectors at the controller (if dual motor) to identify whether the fault follows the motor or stays with the controller.
- If E4 follows the motor: replace/repair the motor or hall sensor assembly.
- If E4 stays with the controller side: replace the controller.
- If wiring and controller check out, test the battery under load; address BMS or connection issues.
Troubleshooting Steps
- Note when E4 occurs: after a bump, during acceleration/braking, or on power-up; record any unusual sounds or vibrations.
- Perform a visual inspection of both motor cables from the axle to the deck; look for cuts, frays, pinching, or crushed insulation and document with photos/video.
- Reseat the motor phase connectors (thick wires) and hall sensor connectors (thin multi-pin) inside the deck; check for corrosion or bent pins.
- Hand-spin each wheel; confirm it spins smoothly and evenly without grinding or tight spots.
- If dual motor, swap left/right motor connectors at the controller; see if E4 moves to the opposite side to isolate motor vs controller.
- If E4 appears only under heavy load, check battery connectors for looseness and test for voltage sag; charge fully and retest.
- If issues persist after reseating and swapping, replace the identified faulty component (motor/hall assembly or controller).