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: Combine sensor inspection
Caution
Be careful and do not allow the lateral-G sensor to fall. If by
chance it is subjected to strong impact, replace it.
1. Connect the connector.
2. Turn ignition switch on, verify the voltage between terminals B and E
under the following conditions.
If not within the specifi ...
Mazda 6 Owners Manual: Inspecting Electrolyte Level
A low level of electrolyte fluid will cause the battery to discharge quickly.
Inspect the electrolyte level at least once a week. If it is low, remove the
caps and add enough distilled water to bring the level between the upper and lower
level (illustration).
Do not overfill.
Examine the sp ...