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: Rear oil seal
REAR OIL SEAL REPLACEMENT
1. Remove the flywheel. (MTX) (See CLUTCH UNIT REMOVAL/INSTALLATION)
2. Remove the drive plate. (ATX) (See DRIVE PLATE REMOVAL/INSTALLATION)
3. Remove in the order indicated in the table.
4. Install in the reverse order of removal.
Rear Oil Seal Installation Note
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Mazda 6 Owners Manual: Air bleeding
Caution
Maintain the fluid level in the reservoir tank properly while
bleeding the air.
Specified fluid
Note
The brakes should be bled whenever a brake line is disconnected.
If a hydraulic line is disconnected at the master cylinder, start at the
slave cylinder farthest from t ...