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: Transaxle fluid temperature (tft) sensor inspection
On-Vehicle Inspection
1. Disconnect the negative battery cable.
2. Remove the air cleaner component. (See INTAKE-AIR SYSTEM
REMOVAL/INSTALLATION.)
Caution
Water or foreign objects entering the connector can cause a poor
connection or corrosion. Be sure not to drop water or foreign object ...
Mazda 6 Service Manual: Dtc c1095, c1096
Caution
When attaching the tester lead to the ABS (ABS/TCS) HU/CM harnesses
connector the SST (49 G066 001) must be used. (See ABS (ABS/TCS) HU/CM
INSPECTION.)
Diagnostic procedure
...