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: Transmitter battery inspection
Caution
Since the battery voltage does not drop fully if the button is
pushed for only 4 seconds or less, it can not be properly examined to see
whether it is good or bad. Always push the button for 5 seconds.
Note
A correct measurement can not be obtained if the battery
temperat ...
Mazda 6 Owners Manual: Customer Assistance (U.S.A.)
Your complete and permanent satisfaction is our business. We are here to serve
you. All Authorized Mazda Dealers have the knowledge and the tools to keep your
Mazda vehicle in top condition.
If you have any questions or recommendations for improvement regarding the service
of your Mazda vehic ...