To use the vanity mirror, lower the sunvisor.
If your vehicle is equipped with a vanity mirror light, it will illuminate when you open the cover.
To prevent the battery from being discharged, the vanity mirror will only illuminate in the tilt range shown in the figure.

Sunvisors
Interior LightsMazda 6 Owners 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.
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Mazda 6 Owners Manual: Blind Spot Monitoring (BSM) (Some models)
The Blind Spot Monitoring (BSM) is designed to assist the driver in checking
the area to the rear of the vehicle on both sides during lane changes by notifying
the driver of the presence of vehicles approaching from the rear in an adjacent
lane.
The Blind Spot Monitoring (BSM) detects vehicle ...