Xiaomi · Hall sensor
18 Xiaomi error code 18
Motor Hall sensor fault
Widely published – may differ by model/firmware
Note
Table published for Xiaomi/Segway-Ninebot scooters; may differ by model/firmware.
Possible causes
General, component-based causes – not a manufacturer-specific statement.
- Failed Hall sensor
- Damaged Hall cable (axle exit, connector)
- Missing Hall supply from the controller
Safe test steps
- Power off and inspect connector and cable, especially at the axle exit.
- Powered, using the known pinout: Hall supply (+) to GND.
- Do all three signal wires toggle low/high when turned slowly by hand?
Workshop reference values
- Hall supply is often ~5 V (controller-specific); signals typically toggle between ~0 V and ~supply.
Repair approach
- Repair cable/connector; replace a failed sensor with the same type and orientation.
- If the Hall supply is missing, check the controller.
Tools needed
- Digital multimeter (CAT III, fused inputs)
- Back-probe pins
- Basic hand tools, insulated screwdrivers
Safety
- For tests with a spinning wheel use a secure work stand with the driven wheel raised.
- Do not try phase/Hall combinations under load.
This information does not replace manufacturer service documentation. Work on batteries and high-voltage parts only with the appropriate expertise.
Related fault codes
10Communication error between dashboard and control board11Abnormal current in motor phase A12Abnormal current in motor phase B13Abnormal current in motor phase C14Throttle fault / not in zero position15Brake lever fault / not in zero position21Battery (BMS) communication fault22BMS password/authentication error