Chevrolet 2009 Avalanche Automobile User Manual


 
Roof-rail airbags are not intended to inflate in rear
impacts. Both roof-rail airbags will deploy when either
side of the vehicle is struck or if the sensing system
predicts that the vehicle is about to roll over, or in
a severe frontal impact.
Your vehicle has a seat position sensor which enables
the sensing system to monitor the position of the
driver’s seat. The seat position sensor provides
information that is used to determine if the airbags
should deploy at a reduced level or at full deployment.
In any particular crash, no one can say whether an
airbag should have inflated simply because of the
damage to a vehicle or because of what the repair costs
were. For frontal airbags, inflation is determined by
what the vehicle hits, the angle of the impact, and how
quickly the vehicle slows down. For roof-rail airbags,
deployment is determined by the location and severity of
the side impact. In a rollover event, roof-rail airbag
deployment is determined by the direction of the roll.
What Makes an Airbag Inflate?
In a deployment event, the sensing system sends
an electrical signal triggering a release of gas from the
inflator. Gas from the inflator fills the airbag causing
the bag to break out of the cover and deploy. The
inflator, the airbag, and related hardware are all part of
the airbag module.
Frontal airbag modules are located inside the
steering wheel and instrument panel. For vehicles
with roof-rail airbags, there are airbag modules in the
ceiling of the vehicle, near the side windows that
have occupant seating positions.
How Does an Airbag 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.
Airbags supplement the protection provided by safety
belts. Frontal airbags distribute the force of the
impact more evenly over the occupant’s upper body,
stopping the occupant more gradually. Roof-rail airbags
distribute the force of the impact more evenly over
the occupant’s upper body.
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