The hazard warning lights should always be used when you stop on or near a roadway in an emergency.

The hazard warning lights warn other drivers that your vehicle is a traffic hazard and that they must take extreme caution when near it.

Depress the hazard warning flasher and all the turn signals will flash. The hazard warning indicator lights in the instrument cluster flash simultaneously.
NOTE
Horn
HomeLink Wireless Control System (Some models)Mazda 6 Owners Manual: Front door speaker removal/installation
1. Disconnect the negative battery cable.
2. Remove the front door trim.
3. Remove in the order indicated in the table.
4. Install in the reverse order of removal.
Front Door Speaker Installation Note
Attach the speaker with the wiring harness placed in the groove of the door
unit panel.
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Mazda 6 Owners Manual: Antilock Brake System (ABS)
The ABS control unit continuously monitors the speed of each wheel. If one wheel
is about to lock up, the ABS responds by automatically releasing and reapplying
that wheel's brake.
The driver will feel a slight vibration in the brake pedal and may hear a chattering
noise from the brake system ...