If the theft-deterrent system detects an inappropriate entry into the vehicle, which could result in the vehicle or its contents being stolen, the alarm alerts the surrounding area of an abnormality by sounding the horn and flashing the hazard warning lights.
The system will not function unless it's properly armed. So when you leave the vehicle, follow the arming procedure correctly.
Mazda 6 Owners Manual: Front brake (disc) removal/installation
1. Remove in the order indicated in the table.
2. Install in the reverse order of removal.
3. After installation, depress the pedal a few times, rotate the wheel by
hand, and verify that the brake does not drag.
Disc Plate Removal Note
Mark the wheel hub bolt and disc plate before removal ...
Mazda 6 Owners Manual: Blind Spot Monitoring (BSM) (Some models)
The Blind Spot Monitoring (BSM) is designed to assist the driver in checking
the area to the rear of the vehicle on both sides during lane changes by notifying
the driver of the presence of vehicles approaching from the rear in an adjacent
lane.
The Blind Spot Monitoring (BSM) detects vehicle ...