GMC 2005 Sierra Denali, Owner'S Manual

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When Should an Airbag Inflate?
The driver’s and right front passenger’s frontal airbags
are designed to inflate in moderate to severe frontal or
near-frontal crashes. But they are designed to inflate only
if the impact exceeds a predetermined deployment
threshold. Deployment thresholds take into account a
variety of desired deployment and non-deployment
events and are used to predict how severe a crash is
likely to be in time for the airbags to inflate and help
restrain the occupants. Whether your frontal airbags will
or should deploy is not based on how fast your vehicle is
traveling. It depends largely on what you hit, the direction
of the impact and how quickly your vehicle slows down.
In addition, your vehicle has “dual stage” frontal airbags,
which adjust the restraint according to crash severity.
Your vehicle is equipped with electronic frontal sensors
which help the sensing system distinguish between a
moderate and a more severe frontal impact. For
moderate frontal impacts, these airbags inflate at a level
less than full deployment. For more severe frontal
impacts, full deployment occurs. If the front of your
vehicle goes straight into a wall that does not move or
deform, the threshold level for the reduced deployment is
about 10 to 16 mph (16 to 25 km/h), and the threshold
level for a full deployment is about 20 to 30 mph
(32 to 48 km/h). (The threshold level can vary, however,
with specific vehicle design, so that it can be somewhat
above or below this range.)
Airbags may inflate at different crash speeds. For
example:
•
If the vehicle hits a stationary object, the airbag
could inflate at a different crash speed than if
the object were moving.
•
If the object deforms, the airbag could inflate at a
different crash speed than if the object does not
deform.
•
If the vehicle hits a narrow object (like a pole) the
airbag could inflate at a different crash speed
than if the vehicle hits a wide object (like a wall).
•
If the vehicle goes into an object at an angle the
airbag could inflate at a different crash speed
than if the vehicle goes straight into the object.
The frontal airbags (driver and right front passenger) are
not intended to inflate during vehicle rollovers, rear
impacts, or in many side impacts because inflation
would not likely help the occupants.
Vehicles with dual stage airbags are also equipped with
special sensors which enable the sensing system to
monitor the position of both the driver and passenger
front seats. The seat position sensor provides
information which is used to determine if the airbags
should deploy at a reduced level or at full deployment.
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