The curtain air bags are mounted in the front and rear window pillars, and the roof edge along both sides.
When the air bag crash sensors detect a side impact of greater than moderate force, the curtain air bag inflates quickly and helps to reduce injury mainly to the rear outboard passenger's head caused by directly hitting interior parts such as a door or window. For more details about air bag deployment, refer to "SRS Air Bag Deployment Criteria".
In a side impact:
Greater than moderate impact to one side of the vehicle will cause the curtain air bag on that side only to inflate.

(With Front Passenger Occupant Classification System) In a roll-over:
In response to a vehicle roll-over, both curtain air bags inflate.

Warning Light/Beep
A system malfunction or operation conditions are indicated by a warning.Refer to Warning/Indicator Lights. Refer to Warning Sound is Activated.
Side Air Bags
SRS Air Bag Deployment CriteriaMazda 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 ...
Mazda 6 Owners Manual: Fuel tank removal/installation
Warning
Repairing a fuel tank that has not been properly steam cleaned can
be dangerous. Explosion or ire may cause death or serious injury. Always
properly steam clean a fuel tank before repairing it.
Fuel line spills and leakage are dangerous. Fuel can ignite and
cause serious injur ...