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: Instrument cluster configuration
1. Connect the SST (WDS or equivalent) to the DLC-2.
2. Input vehicle information following the directions on the screen.
3. Select Module programming.
4. Select Programmable module installation.
5. Select the following items and perform procedures according to directions
on the screen.
...
Mazda 6 Owners Manual: To Turn Off an Armed System
An armed system can be turned off using any one of the following methods:
Pressing the unlock button on the transmitter.
Starting the engine with the push button start.
(With the advanced keyless function)
Pressing a request switch on the doors.
The hazard warning lights will flash twic ...