1. Measure the temperature around the cabin temperature sensor.
2. Measure the resistance between terminals of the cabin temperature sensor.

Cabin temperature sensor removal/installation
Evaporator temperature sensor removal/installationMazda 6 Service Manual: Jacking positions ,vehicle lift (2 supports),safety stands (rigid rack)
positions
Jacking Positions
Warning
Improperly jacking a vehicle is dangerous. The vehicle can slip
off the jack and cause serious injury. Use only the correct front and rear
jacking points and block the wheels.
Use safety stands to support the vehicle after it has been lifted.
Fro ...
Mazda 6 Service Manual: Sst
Some Ford SST or equivalent are used as SSTs necessary for
engine repair. Note that these SSTs are marked with Ford SST
numbers.
Note that a Ford SST number is written together with a
corresponding Mazda SST number as shown below.
Example (section ST)
Example (except section ST)
...