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: Replacing Interior Light Bulbs
Overhead lights/Front map lights (LED type), Rear map lights (LED type)
The LED bulb cannot be replaced as a single unit because it is an integrated
unit. The LED bulb has to be replaced with the unit. We recommend an Authorized
Mazda Dealer when the replacement is necessary.
Overhead lights/F ...
Mazda 6 Service Manual: Theft-deterrent control module inspection
1. Remove the theft-deterrent control module without disconnecting the
connectors.
2. Measure the voltage at the theft-deterrent control module terminals as
indicated below.
3. Disconnect the theft-deterrent control module connector before inspecting
for continuity at terminals L, Q, S, T, a ...