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: Selector lever disassembly/assembly
1. Disassemble in the order shown in the figure.
2. Assemble in the reverse order of disassembly.
Connector Disassembly Note
1. Insert a thin piece of metal from the terminal side of the connector, and
press down the terminal locking tab.
2. Pull the terminal out of the connector. ...
Mazda 6 Service Manual: Inspecting Coolant Level
WARNING
Do not use a match or live flame in the engine compartment. DO NOT ADD
COOLANT WHEN THE ENGINE IS HOT: A hot engine is dangerous. If the engine has
been running, parts of the engine compartment can become very hot. You could be
burned. Carefully inspect the engine coolant in the coola ...