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: Forward Sensing Camera (FSC) (Some models)
Your vehicle is equipped with a Forward Sensing Camera (FSC). The Forward Sensing
Camera (FSC) is positioned near the rearview mirror and used by the following systems.
High Beam Control System (HBC)
Lane-keep Assist System (LAS) & Lane Departure Warning System (LDWS)
Traffic Sign Reco ...
Mazda 6 Service Manual: Sas unit removal/installation
Warning
Handling the SAS unit improperly can accidentally deploy the air
bag modules and pre-tensioner seat belt, which may seriously injure you.
Read AIR BAG SYSTEM SERVICE WARNINGS before handling the SAS unit. (See
SERVICE WARNINGS.)
Caution
When replacing the SAS unit, config ...