How do you replace an ect sensor on a Mazda 6 2003?

To replace the ECT (Engine Coolant Temperature) sensor on a 2003 Mazda 6, first, ensure the engine is cool and disconnect the negative battery terminal. Locate the ECT sensor, which is usually found near the thermostat housing. Remove the electrical connector and unscrew the sensor using a wrench. Install the new sensor, reconnect the electrical connector, and reattach the battery terminal.