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: Cargo compartment light switch inspection
1. Remove the liftgate lower trim. (See LIFTGATE LOWER TRIM
REMOVAL/INSTALLATION)
2. Disconnect the cargo compartment light switch connector.
3. Inspect for continuity between the cargo compartment light switch
terminals using an ohmmeter.
If not as specified, replace the liftgate lock.
...
Mazda 6 Service Manual: Air mix actuator inspection
1. Connect battery positive voltage to terminal D or F and ground to terminal
F or D of the air mix actuator.
2. Verify that the air mix actuator operates as shown below.
If not as specified, replace the air mix actuator.
e
3. Verify that the resistance between the terminals of the ...