E46Forum.co.uk

Posted: **Tue Oct 01, 2024 11:41 am**

How to replace BMW E46 320d (M47D20) coolant temperature sensor?

Tools needed:

22mm deep socket
Coolant drain pan
New coolant temperature sensor (part number: 13621433077)
Coolant (BMW approved)

Replacement procedure:

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

Tips:

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

Note: A faulty coolant temperature sensor can cause poor fuel economy and potential overheating issues. Address any related warning lights promptly.