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: Foreword
When the customer reports a vehicle malfunction, check the malfunction
indicator lamp (MIL) indication and diagnostic trouble code (DTC), then
diagnose the malfunction according to following flowchart.
- If a DTC exists, diagnose the applicable DTC inspection. (See DTC
TABLE.)
- ...
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 ...