BUICK LACROSSE 2009 Repair Manual

The roof-rail airbags for the driver, right front passenger,
and second row outboard passengers, are in the
ceiling above the side windows.
{CAUTION:
If something is between an occupant and an
airbag, the airbag might not inate properly or it
might force the object into that person causing
severe injury or even death. The path of an
inating airbag must be kept clear. Do not put
anything between an occupant and an airbag, and
do not attach or put anything on the steering
wheel hub or on or near any other airbag
covering.
Never secure anything to the roof of a vehicle with
roof-rail airbags by routing a rope or tie down
through any door or window opening. If you do,
the path of an inating roof-rail airbag will be
blocked. Driver Side shown, Passenger Side similar
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When Should an Airbag Inate?
Frontal airbags are designed to inate in moderate to
severe frontal or near-frontal crashes to help reduce the
potential for severe injuries mainly to the driver’s or
right front passenger’s head and chest. However, they
are only designed to inate if the impact exceeds a
predetermined deployment threshold. Deployment
thresholds are used to predict how severe a crash is
likely to be in time for the airbags to inate 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.
Frontal airbags may inate at different crash speeds.
For example:
If the vehicle hits a stationary object, the airbags
could inate at a different crash speed than if the
vehicle hits a moving object.
If the vehicle hits an object that deforms, the
airbags could inate at a different crash speed than
if the vehicle hits an object that does not deform.
If the vehicle hits a narrow object (like a pole), the
airbags could inate 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
airbags could inate at a different crash speed
than if the vehicle goes straight into the object.
Thresholds can also vary with specic vehicle design.
Frontal airbags are not intended to inate during vehicle
rollovers, rear impacts, or in many side impacts.
In addition, your vehicle has dual-stage frontal airbags.
Dual-stage airbags adjust the restraint according to
crash severity. Your vehicle has electronic frontal
sensors, which help the sensing system distinguish
between a moderate frontal impact and a more severe
frontal impact. For moderate frontal impacts, dual-stage
airbags inate at a level less than full deployment.
For more severe frontal impacts, full deployment occurs.
Your vehicle may or may not have roof-rail airbags.
SeeAirbag System on page 1-53. Roof-rail airbags are
intended to inate in moderate to severe side crashes.
Roof-rail airbags will inate if the crash severity is above
the system’s designed threshold level. The threshold
level can vary with specic vehicle design.
Roof-rail airbags are not intended to inate in frontal
impacts, near-frontal impacts, rollovers, or rear impacts.
A roof-rail airbag is intended to deploy on the side of
the vehicle that is struck.
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In any particular crash, no one can say whether an
airbag should have inated simply because of the
damage to a vehicle or because of what the repair costs
were. For frontal airbags, ination 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.
What Makes an Airbag Inate?
In a deployment event, the sensing system sends an
electrical signal triggering a release of gas from the
inator. Gas from the inator lls the airbag causing the
bag to break out of the cover and deploy. The inator, 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.
But airbags would not help in many types of collisions,
primarily because the occupant’s motion is not toward
those airbags. SeeWhen Should an Airbag Inflate? on
page 1-58for more information.
Airbags should never be regarded as anything more
than a supplement to safety belts.
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What Will You See After an Airbag
Inates?
After the frontal airbags inate, they quickly deate, so
quickly that some people may not even realize an
airbag inated. Roof-rail airbags may still be at least
partially inated for some time after they deploy. Some
components of the airbag module may be hot for
several minutes. For location of the airbag modules, see
What Makes an Airbag Inflate? on page 1-59.
The parts of the airbag that come into contact with you
may be warm, but not too hot to touch. There may
be some smoke and dust coming from the vents in the
deated airbags. Airbag ination does not prevent
the driver from seeing out of the windshield or being
able to steer the vehicle, nor does it prevent people from
leaving the vehicle.
{CAUTION:
When an airbag inates, there may be 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 cannot 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.
The vehicle has a feature that may automatically unlock
the doors, turn the interior lamps on, and turn the
hazard warning ashers on when the airbags inate.
You can lock the doors, turn the interior lamps off, and
turn the hazard warning ashers off by using the
controls for those features.
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In many crashes severe enough to inate the 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
the 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 the vehicle covers the need to replace
other parts.
The vehicle has a crash sensing and diagnostic
module which records information after a crash.
SeeVehicle Data Recording and Privacy on
page 7-17andEvent Data Recorders on page 7-17.
Let only qualied technicians work on the airbag
systems. Improper service can mean that an
airbag system will not work properly. See your
dealer/retailer for service.
Passenger Sensing System
The vehicle has a passenger sensing system for the
right front passenger position. The passenger airbag
status indicator will be visible on the instrument
panel when the vehicle is started.
The words ON and OFF
will be visible during the
system check.
If you are using remote start to start your vehicle from a
distance, if equipped, you may not see the system
check. When the system check is complete, either the
word ON or OFF will be visible. SeePassenger
Airbag Status Indicator on page 3-34.
The passenger sensing system will turn off the right
front passenger frontal airbag under certain conditions.
The driver airbag and roof-rail airbags are not affected
by the passenger sensing system.
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The passenger sensing system works with sensors that
are part of the right front passenger seat. The sensors
are designed to detect the presence of a properly-seated
occupant and determine if the right front passenger
frontal airbag should be enabled (may inate) or not.
According to accident statistics, children are safer when
properly secured in a rear seat in the correct child
restraint for their weight and size.
We recommend that children be secured in a rear seat,
including: an infant or a child riding in a rear-facing
child restraint; a child riding in a forward-facing child
seat; an older child riding in a booster seat; and children,
who are large enough, using safety belts.
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 airbag inates. This is because the
back of the rear-facing child restraint would be
very close to the inating airbag. A child in a
forward-facing child restraint can be seriously
injured or killed if the right front passenger airbag
inates and the passenger seat is in a forward
position.
Even if the passenger sensing system has turned
off the right front passenger frontal airbag, no
system is fail-safe. No one can guarantee that
an airbag will not deploy under some unusual
circumstance, even though the airbag is turned off.
Secure rear-facing child restraints in a rear
seat, even if the airbag is off. If you secure a
forward-facing child restraint in the right front seat,
always move the front passenger seat as far back
as it will go. It is better to secure the child restraint
in a rear seat.
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The passenger sensing system is designed to turn off
the right front passenger 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 child restraint.
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
right front passenger frontal airbag, the off indicator
will light and stay lit to remind you that the airbag is off.
SeePassenger Airbag Status Indicator on page 3-34.
The passenger sensing system is designed to turn
on (may inate) the right front passenger frontal airbag
anytime the system senses that a person of adult
size is sitting properly in the right front passenger 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
frontal airbag, depending upon the person’s seating
posture and body build. Everyone in the vehicle who has
outgrown child restraints should wear a safety belt
properly — whether or not there is an airbag for that
person.
{CAUTION:
If the airbag readiness light ever comes on and
stays on, it means that something may be wrong
with the airbag system. To help avoid injury to
yourself or others, have the vehicle serviced right
away. SeeAirbag Readiness Light on page 3-33
for more information, including important safety
information.
1-63

If the On Indicator is Lit for a Child
Restraint
If a child restraint has been installed and the on
indicator is lit:
1. Turn the vehicle off.
2. Remove the child restraint from the vehicle.
3. Remove any additional items from the seat such as
blankets, cushions, seat covers, seat heaters, or
seat massagers.
4. Reinstall the child restraint following the directions
provided by the child restraint manufacturer and
refer toSecuring a Child Restraint in the Right Front
Seat Position on page 1-50.5. If, after reinstalling the child restraint and restarting
the vehicle, the on indicator is still lit, turn the
vehicle off. Then slightly recline the vehicle seatback
and adjust the seat cushion, if adjustable, to
make sure that the vehicle seatback is not pushing
the child restraint into the seat cushion.
Also make sure the child restraint is not trapped
under the vehicle head restraint. If this happens,
adjust the head restraint. SeeHead Restraints
on page 1-6.
6. Restart the vehicle.
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/retailer.
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If the Off Indicator is Lit for an
Adult-Size Occupant
If a person of adult-size is sitting in the right front
passenger seat, but the off indicator is lit, it could be
because that person is not sitting properly in the seat.If this happens, use the following steps to allow the
system to detect that person and enable the right front
passenger frontal airbag:
1. Turn the vehicle off.
2. Remove any additional material from the seat, such
as blankets, cushions, seat covers, seat heaters, or
seat massagers.
3. Place the seatback in the fully upright position.
4. Have the person sit upright in the seat, centered on
the seat cushion, with legs comfortably extended.
5. Restart the vehicle and have the person remain in
this position for two to three minutes after the on
indicator is lit.
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Additional Factors Affecting System
Operation
Safety belts help keep the passenger in position on the
seat during vehicle maneuvers and braking, which
helps the passenger sensing system maintain the
passenger airbag status. See “Safety Belts” and “Child
Restraints” in the Index for additional information
about the importance of proper restraint use.
A thick layer of additional material, such as a blanket or
cushion, or aftermarket equipment such as seat
covers, seat heaters, and seat massagers can affect
how well the passenger sensing system operates.
We recommend that you not use seat covers or other
aftermarket equipment except when approved by GM for
your specic vehicle. SeeAdding Equipment to Your
Airbag-Equipped Vehicle on page 1-67for more
information about modications that can affect how the
system operates.
{CAUTION:
Stowing of articles under the passenger seat or
between the passenger seat cushion and seatback
may interfere with the proper operation of the
passenger sensing system.
Servicing Your Airbag-Equipped
Vehicle
Airbags affect how the vehicle should be serviced.
There are parts of the airbag system in several places
around the vehicle. Your dealer/retailer and the
service manual have information about servicing the
vehicle and the airbag system. To purchase a service
manual, seeService Publications Ordering Information
on page 7-16.
{CAUTION:
For up to 10 seconds after the ignition 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.
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