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: Scheduled Maintenance (U.S.A., Canada, and Puerto Rico)
Follow Schedule 1 if the vehicle is operated mainly where none of the following
conditions (severe driving conditions) apply.
Repeated short-distance driving
Driving in dusty conditions
Driving with extended use of brakes
Driving in areas where salt or other corrosive materials are used
...
Mazda 6 Service Manual: Fuel Economy Monitor
The Control Status and Fuel Consumption are switched and displayed by operating
each icon in the display.
In addition, after completing a trip, the total energy efficiency to date is
displayed in the ending display when the ending display is turned on.
1. Select the icon on the home
screen ...