Tools needed:
- 22mm deep socket
- Coolant drain pan
- New coolant temperature sensor (part number: 13621433077)
- Coolant (BMW approved)
- Allow engine to cool completely
- Drain some coolant from the system
- Locate the sensor on the engine block or thermostat housing
- Disconnect the electrical connector
- Remove old sensor using 22mm deep socket
- Install new sensor (do not overtighten)
- Reconnect electrical connector
- Refill coolant and bleed the system
- Clear any fault codes and test
- Apply a small amount of anti-seize to sensor threads
- Be prepared for some coolant spillage when removing the sensor
- Check for any signs of coolant leaks after installation
