Inspect for continuity between the power outside mirror switch terminals using an ohmmeter.
Mazda 6 Service Manual: Electrical parts
Battery cable
Before disconnecting connectors or removing electrical parts, disconnect
the negative battery cable.
Wiring Harness
To remove the wiring harness from the clip in the
engine room, pry up the hook of the clip using a
flathead screwdriver.
...
Mazda 6 Service Manual: Hill Launch Assist (HLA)
Hill Launch Assist (HLA) is a function which assists the driver in accelerating
from a stop while on a slope. When the driver releases the brake pedal and depresses
the accelerator pedal while on a slope, the function prevents the vehicle from rolling.
The braking force is maintained automatic ...