GMC Chevrolet Tahoe 2003 Manual page 86

Air Bag Systems
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.
The air bag system is designed to work properly under
a wide range of conditions, including off-road usage.
Observe safe driving speeds, especially on rough
terrain. As always, wear your safety belt. See Off-Road
Driving with Your Four-Wheel Drive Vehicle in the
Index for tips on off-road driving.
What Makes an Air Bag Inflate?
In an impact of sufficient severity, the air bag sensing
system detects that the vehicle is in a crash. For both
frontal and side impact air bags, the sensing system
triggers a release of gas from the inflator, which inflates
the air bag. The inflator, the air bag and related hardware
are all part of the air bag modules. Frontal air bag
modules are located inside the steering wheel and
instrument panel. For vehicles with side impact air bags,
the air bag modules are located in the seatback closest to
the driver's and/or right front passenger's door.
1-80
How Does an Air Bag Restrain?
In moderate to severe frontal or near frontal collisions,
even belted occupants can contact the steering wheel or
the instrument panel. In moderate to severe side
collisions, even belted occupants can contact the inside
of the vehicle. The air bag supplements the protection
provided by safety belts. Air bags distribute the force of
the impact more evenly over the occupant's upper
body, stopping the occupant more gradually. But the
frontal air bags would not help you in many types
of collisions, including rollovers, rear impacts, and many
side impacts, primarily because an occupant's motion
is not toward the air bag. Side impact air bags would not
help you in many types of collisions, including frontal
or near frontal collisions, rollovers, and rear impacts,
primarily because an occupant's motion is not toward
those air bags. Air bags should never be regarded
as anything more than a supplement to safety belts, and
then only in moderate to severe frontal or near-frontal
collisions for the driver's and right front passenger's
frontal air bags, and only in moderate to severe
side collisions for vehicles with a driver's and right front
passenger's side impact air bag.