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: Replacing Interior Light Bulbs
Overhead lights/Front map lights (LED type), Rear map lights (LED type)
The LED bulb cannot be replaced as a single unit because it is an integrated
unit. The LED bulb has to be replaced with the unit. We recommend an Authorized
Mazda Dealer when the replacement is necessary.
Overhead lights/F ...
Mazda 6 Owners Manual: Cruise actuator inspection
1. Disconnect the cruise actuator connector.
2. Measure the voltage, continuity and resistance at the cruise actuator
terminals as indicated below.
If not as specified, inspect the parts listed under Action.
If the parts and wiring harnesses are okay but the system still does not
work pr ...