1. Measure the temperature around the water temperature sensor.
2. Measure the resistance between terminals of the water temperature sensor.

Water temperature sensor removal/installation
Refrigerant pressure switch removal/installationMazda 6 Service Manual: Engine coolant temperature (ect) sensor removal/installation
Warning
When the engine is hot, it can badly burn. Turn off the engine and
wait until it is cool before removing the ECT sensor.
1. Drain the engine coolant. (See COOLING SYSTEM SERVICE WARNINGS.)
2. Disconnect the ECT sensor connector.
3. Remove the ECT sensor.
4. Install in the reve ...
Mazda 6 Service Manual: Headlight zeroset
Note
When the configuration is not set for the auto leveling control unit,
headlight zeroset cannot be executed.
1. Adjust the tire air pressure to the specification.
2. Position the unloaded vehicle on a flat, level surface.
3. Connect the SST (WDS or equivalent) to the DLC-2.
4. Turn t ...