When do I need to replace the Xiaomi Scooter Controller?

Here are the main reasons why you may need to replace the controller of your Xiaomi electric scooter:

1. Specific Error Codes (Most common):

   Error 18: If your Xiaomi scooter shows this error, you should first check the motor Hall sensors and their wiring. If they are in good working order (or have been replaced with new ones) and Error 18 persists, this very often indicates a fault in the controller itself.
   Error 40: This error directly indicates a problem with the controller, usually a failure of the temperature sensor on the motherboard or overheating of the controller itself.
   Error 39 (Error 39): indicates an error in the battery temperature sensor. If the sensor and wiring are OK, the problem may be in the controller.
   Other Errors (Less common): Some other errors related to the power supply or the system may indicate a failure of the controller if other parts have been checked. Other error messages can be found here>>

2. Total inoperability of the scooter (“Dead”):

   No Reaction: the scooter does not turn on at all, it is unresponsive, and the battery is charged, the fuse (if any) is in good working order and the connections are intact.

3. Unstable/Improper Operation (When Other Parts Checked):

   Unexpected Shutdown: shuts down while driving, not related to battery, overheating or connectors.
   Self-brake: the scooter brakes for no reason.
   Speed Limit: Speed is limited, although it shouldn’t be.

4. The scooter does not switch off or switches itself on:

   Self-starting: The scooter starts itself shortly after the scooter is switched off, if the dashboard button is not pressed it is usually a controller problem.
   The scooter won’t switch off: If the scooter won’t switch off, this could also be a problem with the controller, before doing so you should check the dashboard for a fault.

5. Physical Damage to the Controller:

   Visible External Damage: cracks, fractures, burnt components, damaged connections.
   Water ingress: Moisture can cause short circuits or corrosion.

6. Modifications/Reprogramming (Not recommended!):

   Unsuccessful “Chipping”: attempts to change the software.
   Too High Load: connecting a motor that is too powerful.