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: i-ELOOP
i-ELOOP is a regenerative braking system. When you depress the brake pedal or
use engine braking, the kinetic energy that occurs is converted to electrical energy
by the power generator and the converted electrical energy is stored in the rechargeable
battery (capacitor and battery). The store ...
Mazda 6 Service Manual: Operation
System triggering conditions
The horn sounds intermittently and the hazard warning lights flash for about
30 seconds when the system is triggered by any one of the following:
Unlocking a door with the key, door lock switch, or an inside door-lock
knob.
Forcing open a door, the hood or th ...