1. Turn off your engine and allow it to cool down for several minutes.
2. Open your hood and locate your car's OBD (on-board diagnostics) port. Mini Coopers usually have their OBD port under the dashboard to the left of the driver's seat.
3. Connect a scan tool or code reader to the OBD port.
4. Turn the key in the ignition to the "ON" position, but do not start the engine.
5. Follow the prompts on the scan tool or code reader to read and clear the trouble codes from the ECU.
6. Once the trouble codes have been cleared, turn the ignition key to the "OFF" position and disconnect the scan tool or code reader from the OBD port.
7. Start the engine and allow it to run for several minutes. If the check engine light turns off, the reset was successful.
