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: If a Warning Light Turns On or Flashes
If any warning light turns on/flashes, take appropriate action for each light.
There is no problem if the light turns off, however if the light does not turn off
or turns on/flashes again, consult an Authorized Mazda Dealer.
The warning contents can be verified on the center display.
1. If the ...
Mazda 6 Owners Manual: Overheating
If the high engine coolant temperature warning light turns on, the vehicle loses
power, or you hear a loud knocking or pinging noise, the engine is probably too
hot.
WARNING
Pull over to a safe location,
then switch the ignition off and make sure the fan is not running before attempting
t ...