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: Blind Spot Monitoring (BSM) (Some models)
The Blind Spot Monitoring (BSM) is designed to assist the driver in checking
the area to the rear of the vehicle on both sides during lane changes by notifying
the driver of the presence of vehicles approaching from the rear in an adjacent
lane.
The Blind Spot Monitoring (BSM) detects vehicle ...
Mazda 6 Service Manual: Refrigerant system service procedures
GAS CHARGING SET INSTALLATION
1. Fully close the valves of the SST (49 C061 001).
2. Connect the SSTs (49 C061 002, 49 C061 003) to the high- and
low-pressure side joints of the SST (49 C061 001).
3. Connect the SSTs (49 C061 006A, 49 C061 007) to the ends of the
SSTs (49 C061 002, 49 C061 00 ...