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: 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 ...
Mazda 6 Service Manual: Discharge headlight service warnings
Discharge headlight bulb service warnings
To prevent electrical shock when replacing the discharge headlight bulb,
dry hands thoroughly, and carry out work in an area out of rain.
When the light switch is on, approx. 25,000 V of high voltage passes
through the discharge headlight bulb so ...