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: Barometric pressure (baro) sensor inspection
Note
Perform the following inspection only when directed.
The following vacuum values are indicated by relative pressure
from the barometric pressure sensor.
1. Connect the SSTs (WDS or equivalent) to the DLC-2.
2. Turn the ignition switch to ON.
3. Select BARO on the SSTs (WDS or equi ...
Mazda 6 Service Manual: Operating Tips
Operate the climate control system with the engine running.
To prevent the battery from being discharged, do not leave the fan control
dial/switch on for a long period of time with the ignition switched ON when
the engine is not running.
Clear all obstructions such as leaves, snow and i ...