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: Rear door garnish installation
Note
Double-sided adhesive tape has already been attached to the new
rear door garnish.
Warning
Using a razor with bare hands can cause injury. Always wear gloves
when using a razor.
1. When installing a new rear door garnish, follow the procedure below:
(1) Remove the adhesi ...
Mazda 6 Service Manual: Ignition switch inspection
1. Disconnect the negative battery cable.
2. Remove the column cover. (See COLUMN COVER REMOVAL/INSTALLATION)
3. Disconnect the ignition switch connectors.
4. Inspect for continuity between the ignition switch terminals using an
ohmmeter.
If not as specified, replace the ignition switch.
...