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: Service cautions
HANDLING INSUFFICIENT REFRIGERANT LEVEL
If an insufficient refrigerant level is detected at troubleshooting,
do not charge (add) the refrigerant. Because an accurate amount of
refrigerant cannot be determined from the pressure indicated on the manifold
gauge, never charge the refrigeran ...
Mazda 6 Service Manual: STEP 1: Contact Your Mazda Dealer
Discuss the matter with an Authorized Mazda Dealer. This is the quickest and
best way to address the issue.
If your concern has not been resolved by the CUSTOMER RELATIONS, SALES,
SERVICE, or PARTS MANAGER, then please contact the GENERAL MANAGER of the dealership
or the OWNER.
If it b ...