GMC ENVOY 2005 Repair Manual

What Makes an Airbag Inate?
In an impact of sufficient severity, the airbag sensing
system detects that the vehicle is in a crash. In the case
of a “rollover capable” roof-mounted airbag, the
sensing system detects that the vehicle is about to roll
over. For both frontal and roof-mounted airbags, the
sensing system triggers a release of gas from the
inator, which inates the airbag. The inator, airbag,
and related hardware are all part of the airbag modules
inside the steering wheel and in the instrument panel
in front of the right front passenger. For vehicles
with roof-mounted airbags, the airbag modules are
located in the ceiling of the vehicle, near the side
windows.
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. The airbag supplements the protection
provided by safety belts. Airbags distribute the force of
the impact more evenly over the occupant’s upper
body, stopping the occupant more gradually. But the
frontal airbags 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 airbag. Roof-mounted airbags
would not help you in many types of collisions, including
frontal or near frontal collisions, and rear impacts,
primarily because an occupant’s motion is not toward
those airbags. Airbags 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 airbags, and only in moderate to severe
side collisions or rollovers for the roof-mounted airbags.
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What Will You See After an Airbag
Inates?
After an airbag inates, it quickly deates, so quickly
that some people may not even realize the airbag
inated. Some components of the airbag module — the
steering wheel hub for the driver’s airbag, the
instrument panel for the right front passenger’s bag or
the ceiling of your vehicle near the side windows — 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 deated airbags. Airbag ination
does not prevent the driver from seeing or being able to
steer the vehicle, nor does it stop people from leaving
the vehicle.
{CAUTION:
When an airbag inates, 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 not get out of the vehicle after an airbag
inates, then get fresh air by opening a
window or a door. If you experience breathing
problems following an airbag deployment, you
should seek medical attention.
Your vehicle has a feature that will automatically unlock
the doors and turn the interior lamps on when the
airbags inate (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 inate an airbag,
windshields are broken by vehicle deformation.
Additional windshield breakage may also occur from the
right front passenger airbag.
Airbags are designed to inate only once. After an
airbag inates, you will need some new parts for
your airbag system. If you do not get them,
the airbag system will not be there to help protect
you in another crash. A new system will include
airbag modules and possibly other parts. The
service manual for your vehicle covers the need to
replace other parts.
Your vehicle is equipped with a crash sensing and
diagnostic module which records information after
a crash. SeeVehicle Data Collection and Event
Data Recorders on page 7-10.
Let only qualied technicians work on your airbag
system. Improper service can mean that your
airbag system will not work properly. See your
dealer for service.
Notice:If you damage the covering for the driver’s
or the right front passenger’s airbag, or the side
impact airbag covering on the ceiling near the side
windows, the airbag may not work properly. You
may have to replace the airbag module in the
steering wheel, both the airbag module and the
instrument panel for the right front passenger’s
airbag, or side impact airbag module and ceiling
covering for the roof-mounted side impact airbag.
Do not open or break the airbag coverings.
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Passenger Sensing System
Your vehicle has a passenger sensing system for the
right front passenger’s position. A passenger airbag
status indicator in the rearview mirror will be visible
when you turn your ignition key to START or RUN. The
words ON and OFF or the symbol for on and off, will
be visible on the rearview mirror during the system
check. When the system check is complete, either the
word ON or the word OFF, or the symbol for on or
the symbol for off will be visible. SeePassenger Airbag
Status Indicator on page 3-37.The passenger sensing system will turn off the right
front passenger’s frontal airbag under certain conditions.
The driver’s airbag and the side airbags are not part
of the passenger sensing system.
Passenger Airbag Status Indicator – United States
Passenger Airbag Status Indicator – Canada
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The passenger sensing system works with sensors that
are part of the right front passenger’s seat and safety
belt. The sensors are designed to detect the presence of
a properly-seated occupant and determine if the
passenger’s frontal airbag should be enabled (may
inate) or not.
Accident statistics show that children are safer if they
are restrained in the rear rather than the front seat.
General Motors recommends that child restraints
be secured in a rear seat, 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.
Your vehicle has a rear seat that will accommodate
a rear-facing child restraint. A label on your sun visor
says, “Never put a rear-facing child seat in the
front.” This is because the risk to the rear-facing child is
so great, if the airbag deploys.
{CAUTION:
A child in a rear-facing child restraint can be
seriously injured or killed if the right front
passenger’s airbag inates.
CAUTION: (Continued)
CAUTION: (Continued)
This is because the back of the rear-facing
child restraint would be very close to the
inating airbag.
Even though the passenger sensing system is
designed to turn off the passenger’s frontal
airbag if the system detects a rear-facing child
restraint, no system is fail-safe, and no one can
guarantee that an airbag will not deploy under
some unusual circumstance, even though it is
turned off. General Motors recommends that
rear-facing child restraints be secured in the
rear seat, even if the airbag is off.
The passenger sensing system is designed to turn off
the right front passenger’s frontal airbag if:
the right front passenger seat is unoccupied
the system determines that an infant is present in a
rear-facing infant seat
the system determines that a small child is present
in a forward-facing child restraint
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the system determines that a small child is present
in a booster seat
a right front passenger takes his/her weight off of
the seat for a period of time
the right front passenger seat is occupied by a
smaller person, such as a child who has outgrown
child restraints
or if there is a critical problem with the airbag
system or the passenger sensing system.
When the passenger sensing system has turned off the
passenger’s frontal airbag, the off indicator in the
rearview mirror will light and stay lit to remind you that
the airbag is off.
If a child restraint has been installed and the on
indicator is lit, turn the vehicle off. Remove the child
restraint from the vehicle and reinstall the child restraint
following the child restraint manufacturer’s directions
and refer toSecuring a Child Restraint in the Right Front
Seat Position on page 1-43.If after reinstalling the child restraint and restarting the
vehicle, the on indicator is still lit, check to make
sure that the vehicle’s seatback is not pressing the child
restraint into the seat cushion. If this happens, slightly
recline the vehicle’s seatback and adjust the seat
cushion if possible. Also make sure the child restraint is
not trapped under the vehicle head restraint. If this
happens, adjust the head restraint.
If the on indicator is still lit, secure the child in the child
restraint in a rear seat position in the vehicle and
check with your dealer.
The passenger sensing system is designed to enable
(may inate) the right front passenger’s frontal
airbag anytime the system senses that a person of adult
size is sitting properly in the right front passenger’s
seat. When the passenger sensing system has allowed
the airbag to be enabled, the on indicator will light
and stay lit to remind you that the airbag is active.
For some children who have outgrown child restraints
and for very small adults, the passenger sensing system
may or may not turn off the right front passenger’s
frontal airbag, depending upon the person’s seating
posture and body build. Everyone in your vehicle who
has outgrown child restraints should wear a safety
belt properly — whether or not there is an airbag for
that person.
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If a person of adult-size is sitting in the right front
passenger’s seat, but the off indicator is lit, it could be
because that person is not sitting properly in the seat. If
this happens, turn the vehicle off and ask the person to
place the seatback in the fully upright position, then sit
upright in the seat, centered on the seat cushion, with the
person’s legs comfortably extended. Restart the vehicle
and have the person remain in this position for about two
minutes. This will allow the system to detect that person
and then enable the passenger’s airbag.
{CAUTION:
If the airbag readiness light in the instrument
panel cluster ever comes on and stays on, it
means that something may be wrong with the
airbag system. If this ever happens, have the
vehicle serviced promptly, because an
adult-size person sitting in the right front
passenger’s seat may not have the protection
of the frontal airbag. SeeAirbag Readiness
Light on page 3-36for more on this, including
important safety information.
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Aftermarket equipment, such as seat covers, can affect
how well the passenger sensing system operates.
You may want to consider not using seat covers or other
aftermarket equipment if your vehicle has the passenger
sensing system. SeeAdding Equipment to Your
Airbag-Equipped Vehicle on page 1-63for more
information about modications that can affect how the
system operates.
{CAUTION:
Stowing of articles under the passenger’s seat
or between the passenger’s seat cushion and
seatback may interfere with the proper
operation of the passenger sensing system.
Servicing Your Airbag-Equipped
Vehicle
Airbags affect how your vehicle should be serviced.
There are airbag system parts in several places around
your vehicle. You do not want the system to inate
while someone is working on your vehicle. Your dealer
and the service manual have information about
servicing your vehicle and the airbag system. To
purchase a service manual, seeService Publications
Ordering Information on page 7-13.
{CAUTION:
For up to 10 seconds after the ignition key is
turned off and the battery is disconnected, an
airbag can still inate during improper service.
You can be injured if you are close to an
airbag when it inates. Avoid yellow
connectors. They are probably part of the
airbag system. Be sure to follow proper
service procedures, and make sure the person
performing work for you is qualied to do so.
The airbag system does not need regular maintenance.
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Adding Equipment to Your
Airbag-Equipped Vehicle
Q:Is there anything I might add to the front or
sides of the vehicle that could keep the
airbags from working properly?
A:Yes. If you add things that change your vehicle’s
frame, bumper system, front end or side sheet metal
or height, they may keep the airbag system from
working properly. Also, the airbag system may not
work properly if you relocate any of the airbag
sensors. If you have any questions about this, you
should contact Customer Assistance before you
modify your vehicle. The phone numbers and
addresses for Customer Assistance are
in Step Two of the Customer Satisfaction Procedure
in this manual. SeeCustomer Satisfaction Procedure
on page 7-2.
Q:Because I have a disability, I have to get my
vehicle modied. How can I nd out whether
this will affect my airbag system?
A:Changing or moving any parts of the front seats,
safety belts, the airbag sensing and diagnostic
module (located under the driver’s seat), or
the inside rearview mirror can affect the operation
of the airbag system. If you have questions,
call Customer Assistance. The phone numbers and
addresses for Customer Assistance are in Step
Two of the Customer Satisfaction Procedure in this
manual. SeeCustomer Satisfaction Procedure
on page 7-2.
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Restraint System Check
Checking Your Restraint Systems
Now and then, make sure the safety belt reminder light
and all your belts, buckles, latch plates, retractors
and anchorages are working properly. Look for any other
loose or damaged safety belt system parts. If you see
anything that might keep a safety belt system from doing
its job, have it repaired.
Torn or frayed safety belts may not protect you in a
crash. They can rip apart under impact forces. If a belt
is torn or frayed, get a new one right away.
Also look for any opened or broken airbag covers, and
have them repaired or replaced. (The airbag system
does not need regular maintenance.)
Replacing Restraint System Parts
After a Crash
{CAUTION:
A crash can damage the restraint systems in
your vehicle. A damaged restraint system may
not properly protect the person using it,
resulting in serious injury or even death in a
crash. To help make sure your restraint
systems are working properly after a crash,
have them inspected and any necessary
replacements made as soon as possible.
If you have had a crash, do you need new belts or
LATCH system parts?
After a very minor collision, nothing may be necessary.
But if the belts were stretched, as they would be if
worn during a more severe crash, then you need
new parts.
If the LATCH system was being used during a more
severe crash, you may need new LATCH system parts.
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