2002 GMC ENVOY Air bag

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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
ªthreshold level.º
In addition, your vehicle has ªdual stageº frontal air bags,
which adjust the amount of restraint according to crash
severity. For moderate frontal impacts, these air bags
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 doesn't
move or deform, the threshold level for the reduced
deployment is about 12 to 16 mph (19 to 26 km/h),
and the threshold level for a full deployment is about
16 to 25 mph (26 to 40 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.
The 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 ªthreshold level.º 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.

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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 ªOff
-Road
Drivingº in the Index for more 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, air bag and related hardware
are all part of the air bag modules inside the steering
wheel, instrument panel and the side of the front
seatbacks closest to the door.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 the driver's and
right front passenger's side impact air bags.

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What will you see after an air bag inflates?
After an air bag inflates, it quickly deflates, so quickly
that some people may not even realize the air bag
inflated. Some components of the air bag module
-- the
steering wheel hub for the driver's air bag, the
instrument panel for the right front passenger's bag, the
side of the seatback closest to the door for the driver and
right front passenger's side impact air bags
-- will be
hot for a short time. The parts of the bag that come into
contact with you may be warm, but not too hot to touch.
There will be some smoke and dust coming from the
vents in the deflated air bags. Air bag inflation doesn't
prevent the driver from seeing or being able to steer the
vehicle, nor does it stop people from leaving the vehicle.
CAUTION:
When an air bag inflates, there is dust in the air.
This dust could cause breathing problems for
people with a history of asthma or other
breathing trouble. To avoid this, everyone in the
vehicle should get out as soon as it is safe to do so.
If you have breathing problems but can't get out
of the vehicle after an air bag inflates, then get
fresh air by opening a window or a door.
Your vehicle has a feature that will automatically unlock
the doors and turn the interior lamps on when the air
bags inflate (if battery power is available). You can lock
the doors again and turn the interior lamps off by using
the door lock and interior lamp controls.

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In many crashes severe enough to inflate an air bag,
windshields are broken by vehicle deformation.
Additional windshield breakage may also occur from
the right front passenger air bag.

Air bags are designed to inflate only once. After an
air bag inflates, you'll need some new parts for your
air bag system. If you don't get them, the air bag
system won't be there to help protect you in another
crash. A new system will include air bag modules
and possibly other parts. The service manual for
your vehicle covers the need to replace other parts.

Your vehicle is equipped with an electronic frontal
sensor, which helps the sensing system distinguish
between a moderate frontal impact and a more
severe frontal impact. Your vehicle is also equipped
with a crash sensing and diagnostic module, which
records information about the frontal air bag system.
The module records information about the readiness
of the system, when the system commands air bag
inflation and driver's safety belt usage at deployment.
The module also records speed, engine rpm, brake
and throttle data.

Let only qualified technicians work on your air
bag systems. Improper service can mean that an
air bag system won't work properly. See your dealer
for service.
NOTICE:
If you damage the covering for the driver's
or the right front passenger's air bag, or the
air bag covering on the driver's and right front
passenger's seatback, the bag may not work
properly. You may have to replace the air bag
module in the steering wheel, both the air bag
module and the instrument panel for the right
front passenger's air bag, or both the air bag
module and seatback for the driver's and right
front passenger's side impact air bag. Do not
open or break the air bag coverings.

1-30 Servicing Your Air Bag-Equipped Vehicle
Air bags affect how your vehicle should be serviced.
There are parts of the air bag systems in several places
around your vehicle. Your dealer and the service manual
have information about servicing your vehicle and the
air bag systems. To purchase a service manual, see
ªService and Owner Publicationsº in the Index.
CAUTION:
For up to 10 seconds after the ignition key is
turned off and the battery is disconnected, an air
bag can still inflate during improper service. You
can be injured if you are close to an air bag when
it inflates. Avoid yellow connectors. They are
probably part of the air bag systems. Be sure to
follow proper service procedures, and make sure
the person performing work for you is qualified
to do so.
The air bag systems do not need regular maintenance.
Rear Seat Passengers
It's very important for rear seat passengers to buckle up!
Accident statistics show that unbelted people in the rear
seat are hurt more often in crashes than those who are
wearing safety belts.
Rear passengers who aren't safety belted can be thrown
out of the vehicle in a crash. And they can strike others
in the vehicle who are wearing safety belts.
Rear Seat Passenger Positions

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CAUTION:
Children who are up against, or very close to, any
air bag when it inflates can be seriously injured
or killed. Air bags plus lap
-shoulder belts offer
outstanding protection for adults and older
children, but not for young children and infants.
Neither the vehicle's safety belt system nor its air
bag system is designed for them. Young children
and infants need the protection that a child
restraint system can provide.
Q:What are the different types of add-on
child restraints?
A:Add-on child restraints, which are purchased by
the vehicle's owner, are available in four basic
types. Selection of a particular restraint should take
into consideration not only the child's weight,
height and age but also whether or not the restraint
will be compatible with the motor vehicle in which
it will be used.
For most basic types of child restraints, there are
many different models available. When purchasing
a child restraint, be sure it is designed to be used in
a motor vehicle. If it is, the restraint will have a
label saying that it meets federal motor vehicle
safety standards.
The restraint manufacturer's instructions that come
with the restraint state the weight and height
limitations for a particular child restraint. In
addition, there are many kinds of restraints
available for children with special needs.

1-42 Where to Put the Restraint
Accident statistics show that children are safer if they
are restrained in the rear rather than the front seat.
General Motors, therefore, recommends that child
restraints be secured in a rear seat outside position
including an infant riding in a rear
-facing infant seat, a
child riding in a forward
-facing child seat and an older
child riding in a booster seat. Never put a rear
-facing
child restraint in the front passenger seat. Here's why:
CAUTION:
A child in a rear-facing child restraint can be
seriously injured or killed if the right front
passenger's air bag inflates. This is because the
back of the rear
-facing child restraint would
be very close to the inflating air bag. Always
secure a rear
-facing child restraint in a rear seat
outside position.
You may secure a forward-facing child restraint
in the right front seat, but before you do, always
move the front passenger seat as far back as it
will go. It's better to secure the child restraint in
a rear seat outside position.
Wherever you install it, be sure to secure the child
restraint properly.
Keep in mind that an unsecured child restraint can move
around in a collision or sudden stop and injure people in
the vehicle. Be sure to properly secure any child
restraint in your vehicle
-- even when no child is in it.

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If your child restraint is equipped with the LATCH
system, see ªLower Anchorages and Top Tethers for
Children (LATCH)º in the Index.
Your vehicle has a right front passenger air bag. Never
put a rear
-facing child restraint in this seat. Here's why:
CAUTION:
A child in a rear-facing child restraint can be
seriously injured or killed if the right front
passenger's air bag inflates. This is because the
back of the rear
-facing child restraint would be
very close to the inflating air bag. Always secure
a rear
-facing child restraint in the rear seat.
Although a rear seat is a safer place, you can secure a
forward
-facing child restraint in the right front seat.You'll be using the lap
-shoulder belt. See the earlier
part about the top strap if the child restraint has one.
Be sure to follow the instructions that came with the
child restraint. Secure the child in the child restraint
when and as the instructions say.
1. Because your vehicle has a right front passenger air
bag, always move the seat as far back as it will go
before securing a forward
-facing child restraint.
See ªSeatsº in the Index.
2. Put the restraint on the seat.
3. Pick up the latch plate, and run the lap and shoulder
portions of the vehicle's safety belt through or
around the restraint. The child restraint instructions
will show you how.
If the shoulder belt goes in front of the child's face
or neck, put it behind the child restraint.