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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).
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