1. Remove the climate control unit.
2. Inspect for continuity between the fan switch terminals using an ohmmeter.


Climate control unit inspection
Defroster switch inspectionMazda 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 ...
Mazda 6 Service Manual: Overheating
If the high engine coolant temperature warning light turns on, the vehicle loses
power, or you hear a loud knocking or pinging noise, the engine is probably too
hot.
WARNING
Pull over to a safe location,
then switch the ignition off and make sure the fan is not running before attempting
t ...