2009 BUICK LACROSSE sensor

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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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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Adding Equipment to Your
Airbag-Equipped Vehicle
Q:Is there anything I might add to or change
about the vehicle that could keep the airbags
from working properly?
A:Yes. If you add things that change the vehicle’s
frame, bumper system, height, front end or side
sheet metal, they may keep the airbag system from
working properly. Changing or moving any parts
of the front seats, safety belts, the airbag sensing
and diagnostic module, steering wheel, instrument
panel, roof-rail airbag modules, ceiling headliner
or pillar garnish trim, front sensors, or airbag wiring
can affect the operation of the airbag system.
In addition, the vehicle has a passenger sensing
system for the right front passenger position, which
includes sensors that are part of the passenger’s
seat. The passenger sensing system may not
operate properly if the original seat trim is replaced
with non-GM covers, upholstery or trim, or with
GM covers, upholstery or trim designed for a
different vehicle. Any object, such as an aftermarket
seat heater or a comfort enhancing pad or device,
installed under or on top of the seat fabric,
could also interfere with the operation of thepassenger sensing system. This could either
prevent proper deployment of the passenger
airbag(s) or prevent the passenger sensing system
from properly turning off the passenger airbag(s).
SeePassenger Sensing System on page 1-61.
If you have any 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.
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: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. See
Customer Satisfaction Procedure on page 7-2.
In addition, your dealer/retailer and the service manual
have information about the location of the airbag
sensors, sensing and diagnostic module and airbag
wiring.
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Object Detection Systems
Ultrasonic Rear Parking
Assist (URPA)
For vehicles with the Ultrasonic Rear Parking Assist
(URPA) system, it operates at speeds less than 3 mph
(5 km/h), and assists the driver with parking and
avoiding objects while in R (Reverse). The sensors on
the rear bumper are used to detect the distance to
an object up to 5 feet (1.5 m) behind the vehicle, and at
least 10 inches (25.4 cm) off the ground.
{CAUTION:
The Ultrasonic Rear Parking Assist (URPA)
system does not replace driver vision. It cannot
detect:
objects that are below the bumper,
underneath the vehicle, or if they are too
close or far from the vehicle
children, pedestrians, bicyclists, or pets.
If you do not use proper care before and while
backing; vehicle damage, injury, or death could
occur. Even with URPA, always check behind the
vehicle before backing up. While backing, be sure
to look for objects and check the vehicle’s mirrors.
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When the System Does Not Seem to
Work Properly
The ultrasonic sensors are not clean, a red URPA
display light may illuminate when the vehicle is in
R (Reverse). Keep the rear bumper free of
mud, dirt, snow, ice and slush. For cleaning
instructions, seeWashing Your Vehicle on
page 5-93.
A trailer was attached to the vehicle, or a bicycle or
an object was hanging out of the trunk during the
last drive cycle, the red light may illuminate.
Once the attached object is removed, URPA will
return to normal operation.
A tow bar is attached to the vehicle.
The vehicle’s bumper is damaged. Take the vehicle
to your dealer/retailer to repair the system.
Other conditions may affect system performance,
such as vibrations from a jackhammer or the
compression of air brakes on a very large truck.
If the system is still disabled, after driving forward at
least 15 mph (25 km/h), take the vehicle to your
dealer/retailer.
OnStar®System
OnStar uses several innovative technologies and live
advisors to provide a wide range of safety, security,
information, and convenience services. If the airbags
deploy, the system is designed to make an automatic
call to OnStar Emergency advisors who can request
emergency services be sent to your location. If
the keys are locked in the vehicle, call OnStar at
1-888-4-ONSTAR to have a signal sent to unlock
the doors. OnStar Hands-Free Calling, including
30 trial minutes good for 60 days, is available on most
vehicles. OnStar Turn-by-Turn Navigation service,
with one trial route, is available on most vehicles. Press
the OnStar button to have an OnStar advisor contact
Roadside Service.
OnStar service is provided subject to the OnStar Terms
and Conditions included in the OnStar Subscriber
glove box literature.
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2(Headlamps):Turn the control to this position to
turn on the headlamps together with the following lamps
listed below.
A warning chime will sound if the driver’s door is
opened when the ignition switch is turned to LOCK/OFF
or ACC/ACCESSORY and the headlamps or parking
lamps are on.
Parking Lamps
Taillamps
License Plate Lamps
Instrument Panel Lights
#(Fog lamps) (If Equipped):Push the fog lamps
button to turn them on and off. SeeFog Lamps
on page 3-15for additional information.
Daytime Running Lamps (DRL)/
Automatic Headlamp System
Daytime Running Lamps (DRL) can make it easier for
others to see the front of your vehicle during the day.
DRL can be helpful in many different driving conditions,
but they can be especially helpful in the short periods
after dawn and before sunset. DRL lamps are required
to function at all times on all vehicles rst sold in Canada.
A light sensor on top of the instrument panel makes the
DRL work, so be sure it is not covered.
The DRL system will make the low-beam headlamps
come on at reduced brightness when the following
conditions are met:
The ignition is on.
The exterior lamps control is off.
The parking brake is released.
While the DRL are on, only the vehicle’s low-beam
headlamps will be on at reduced brightness. The turn
signal, taillamps, sidemarker, and other lamps will not
be on. The instrument panel will not be lit up either.
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3. Wait for the system to regulate. This may take from
10 to 30 minutes. Then, adjust the temperature,
if necessary.
Do not cover the solar sensor located in the
center of the instrument panel, near the windshield.
For more information on the solar sensor, see
“Sensors” later in this section.
4. Press OFF to turn the climate control system off.
Only the rear defog and heated seats will function.
Press AUTO or any other button except the heated
seats or rear defog to turn the climate control system
back on.
This control has four types of operation.
Automatic can set/change the temperature only.
AUTO and temperature only will appear on the
display.
Semi-Automatic Fan can set/change the
temperature and mode. The fan operates
automatically. The temperature and mode
will appear on the display.
Semi-Automatic Mode can set/change the
temperature and fan speed. The mode operates
automatically. The fan speed and temperature
will appear on the display.
Manual can set/change the temperature, mode and
fan. The fan speed, temperature, and mode will
appear on the display.For vehicles with the remote start feature, the climate
control system automatically regulates the inside
temperature of the vehicle when the remote start system
is activated. Normal operation and the last setting of
the climate control system will return after the key
is turned on.
Manual Operation
During daylight hours, the instrument panel brightness
control might need to be adjusted to the highest setting,
in order to see the indicator lights for the various
climate control settings.
OFF:Press to turn the climate control system off.
yz(Temperature):Press to manually adjust the
temperature inside the vehicle. Press
yorzon the
driver or passenger side to increase or decrease the
temperature. The display will show the selected
temperature.
z9/9y(Fan Control):Press the fan control
buttons to increase or decrease the fan speed. Pressing
the arrows cancels the automatic operation and places
the system in manual or semi-automatic mode. Press the
AUTO button to return to automatic operation. If the
airow seems low when the fan is at the highest setting,
the passenger compartment air lter may need to
be replaced. For more information seePassenger
Compartment Air Filter on page 3-29andScheduled
Maintenance on page 6-4.
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Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog or frost from the rear window. The rear
window defogger will only work when the engine
is running.
=(Rear Window Defogger):Press to turn the rear
window defogger on and off. Be sure to clear as much
snow from the rear window as possible.
The rear window defogger turns off about 20 minutes
after the button is pressed. If turned on again, the
defogger only runs for about 20 minutes before turning
off. The defogger can also be turned off by turning
off the engine.
The heated outside rearview mirrors, help to clear fog or
frost from the surface of the mirror when the rear window
defog button is pressed.
Do not drive the vehicle until all the windows are clear.
Notice:Do not use a razor blade or sharp object to
clear the inside rear window. Do not adhere anything
to the defogger grid lines in the rear glass. These
actions may damage the rear defogger. Repairs
would not be covered by your warranty.
((Heated Seats):Press to turn the driver or
passenger heated seats on and off. SeeHeated
Seats on page 1-3for additional information.
Sensors
The solar sensor on the vehicle monitors the solar heat
and the air inside of the vehicle. This information is used
to maintain the selected temperature by initiating needed
adjustments to the temperature, the fan speed, and the
air delivery system. The system may also supply cooler
air to the side of the vehicle facing the sun. The
recirculation mode will also be activated, as necessary.
Do not cover the solar sensor located in the center of the
instrument panel, near the windshield, or the system will
not work properly.
Outlet Adjustment
Use the thumbwheels located between the center
outlets to open and close the outlets. Move the lever
in the center of each air outlet to adjust the direction
of the airow.
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