GM None Pontiac Aztek - Manual (Page 73)

When Should an Air Bag Inflate?
The driver’s and right front passenger’s frontal air bags
are designed to inflate in moderate to severe frontal
or near-frontal crashes. But they are designed to inflate
only if the impact speed is above the system’s
designed “threshold level.”
If your vehicle goes straight into a wall that doesn’t
move or deform, the threshold level is about 12
to 19 mph (19 to 31 km/h). The threshold level can vary,
however, with specific vehicle design, so that it can
be somewhat above or below this range.
If your vehicle strikes something that will move or
deform, such as a parked car, the threshold level will be
higher. The driver’s and right front passenger’s frontal
air bags are not designed to inflate in rollovers, rear
impacts, or in many side impacts because inflation
would not help the occupant.
Your vehicle may or may not have a side impact air
bag. See Air Bag Systems on page 1-61. Side impact air
bags are designed to inflate in moderate to severe
side crashes. A side impact air bag will inflate if
the crash severity is above the system’s designed
“threshold level.” The threshold level can vary with
specific vehicle design. Side impact air bags are
not designed to inflate in frontal or near-frontal impacts,
rollovers or rear impacts, because inflation would not
help the occupant. A side impact air bag will only deploy
on the side of the vehicle that is struck.
In any particular crash, no one can say whether an air
bag should have inflated simply because of the damage
to a vehicle or because of what the repair costs were.
For frontal air bags, inflation is determined by the angle
of the impact and how quickly the vehicle slows down
in frontal and near-frontal impacts. For side impact
air bags, inflation is determined by the location
and severity of the impact.
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