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
Flat TireMazda 6 Owners Manual: Changing a Flat Tire
NOTE
If the following occurs while driving, it could indicate a flat tire.
Steering becomes difficult.
The vehicle begins to vibrate excessively.
The vehicle pulls in one direction.
If you have a flat tire, drive slowly to a level spot that is well off the road
and out of the way of tr ...
Mazda 6 Owners Manual: Expansion valve removal/installation
1. Disconnect the negative battery cable.
2. Discharge the refrigerant from the system. (See RECOVERY.) (See CHARGING.)
Caution
If moisture or foreign material enters the refrigeration cycle,
cooling ability will be lowered and abnormal noise will occur. Always
immediately plug open fitt ...