The High Beam Control System (HBC) operates to switch the headlights automatically between high and low beams after the ignition is switched ON and the headlight switch is in the AUTO and high beam position.
The High Beam Control System (HBC) determines that it is dark based on the brightness of the surrounding area. At the same time, the High Beam Control System (HBC) indicator light (green) in the instrument cluster illuminates.

NOTE
When the vehicle speed is less than about 20 km/h (12 mph), the High Beam Control System (HBC) switches the headlights to low beams.
High Beam Control System (HBC) (Some models)
Manual SwitchingMazda 6 Owners Manual: Variable intake-air system (vis) control solenoid valve inspection (l3)
1. Remove the VIS control solenoid valve. (See INTAKE-AIR SYSTEM
REMOVAL/INSTALLATION.)
2. Inspect airflow between the ports under the following conditions.
If not as specified, replace the VIS control solenoid valve.
If as specified, carry out the Circuit Open/Short Inspection.
Circ ...
Mazda 6 Owners Manual: Rearview Mirror
WARNING
Do not stack cargo or objects higher than the seatbacks: Cargo stacked
higher than the seatbacks is dangerous. It can block your view in the rearview mirror,
which might cause you to hit another car when changing lanes.
Rearview mirror adjustment
Before driving, adjust the rearview mi ...