2009 CHEVROLET AVALANCHE 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 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 1-62. Roof-rail airbags are
intended to inate in moderate to severe side crashes.
In addition, these roof-rail airbags are intended to inate
during a rollover or in a severe frontal impact. 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.
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Roof-rail airbags are not intended to inate in rear
impacts. Both roof-rail airbags will deploy when either
side of the vehicle is struck or if the sensing system
predicts that the vehicle is about to roll over, or in
a severe frontal impact.
Your vehicle has a seat position sensor which enables
the sensing system to monitor the position of the
driver’s seat. The seat position sensor provides
information that is used to determine if the airbags
should deploy at a reduced level or at full deployment.
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. In a rollover event, roof-rail airbag
deployment is determined by the direction of the roll.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.
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The passenger sensing system works with sensors that
are part of the right front passenger seat and safety
belt. 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 the 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
CAUTION: (Continued)
CAUTION: (Continued)
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.
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 an infant is present in a
child restraint.
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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, overhead console, front
sensors, side impact sensors, rollover sensor
module, 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
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 the passenger
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). See
Passenger Sensing System on page 1-70.
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.
If the vehicle has rollover roof-rail airbags, see
Different Size Tires and Wheels on page 5-73for
additional important information.
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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Outside Heated Mirrors
<(Rear Window Defogger):Press to heat the
mirrors.
See “Rear Window Defogger” underDual Automatic
Climate Control System on page 3-23for more
information.
Object Detection Systems
Ultrasonic Rear Parking
Assist (URPA)
For vehicles with the Ultrasonic Rear Parking Assist
(URPA) system, it operates at speeds less than 5 mph
(8 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 8 feet (2.5 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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The system can be
disabled by pressing the
rear park aid disable button
located next to the radio.
The indicator light will come on and PARK ASSIST OFF
displays on the Driver Information Center (DIC) to
indicate that URPA is off, seeDIC Warnings and
Messages on page 3-58for information about clearing
the message.
Notice:If you use URPA while the tailgate is
lowered, it may not detect an object behind your
vehicle, and you might back into the object and
damage your vehicle. Always verify the tailgate is
closed when using URPA or turn off URPA when
driving with the tailgate lowered.When the System Does Not Seem to
Work Properly
If the URPA system will not activate due to a temporary
condition, the message PARK ASSIST OFF will be
displayed on the DIC and a red light will be shown on the
rear URPA display when the shift lever is moved into R
(Reverse). This occurs under the following conditions:
The driver disables the system.
The ultrasonic sensors are not clean. Keep the
vehicle’s rear bumper free of mud, dirt, snow, ice and
slush. For cleaning instructions, seeWashing Your
Vehicle on page 5-103.
A trailer was attached to the vehicle, or a bicycle or
an object was hanging out of the tailgate during the
last drive cycle, the red light may illuminate in the
rear display. 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.
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Windshield Wipers
Turn the band with the wiper symbol to control the
windshield wipers.
8(Mist):Turn to mist for a single wiping cycle. Hold it
there until the wipers start. Then let go. The wipers
stop after one wipe. Hold the band on mist longer, for
more wipe cycles.
9(Off):Turns the wipers off.
6(Delay):Turn the band to adjust the delay time. The
delay between wiping cycles becomes shorter as
the band is moved to the top of the lever. This can be
very useful in light rain or snow.
6(Low Speed):For steady wiping at low speed.
?(High Speed):For high-speed wiping.
Clear ice and snow from the wiper blades before using
them. If they are frozen to the windshield, gently
loosen or thaw them. Damaged wiper blades may not
clear the windshield well, making it harder to see
and drive safely. If the blades do become damaged,
install new blades or blade inserts. For more information,
seeWindshield Wiper Blade Replacement on page 5-54.Heavy snow or ice can overload the wiper motor. A
circuit breaker will stop the motor until it cools down.
Clear away snow or ice to prevent an overload.
Rainsense™ II Wipers
For vehicles with Rainsense™ II windshield wipers, the
moisture sensor is located next to the inside rearview
mirror and is mounted on the windshield. When active,
these sensors are able to detect moisture on the
windshield and automatically turn on the wipers.
To turn on the Rainsense feature, the wipers must be
set to one of the ve delay settings on the multifunction
lever. Each of the ve settings adjusts the sensitivity
of the sensor.
Since different drivers have different setting
preferences, it is recommended that the mid-range
setting (position 3) be used initially. For more wipes,
select the higher settings; for fewer wipes, select
the lower settings located closer to the off position
on the multifunction lever.
The sensor will automatically control the frequency of
the wipes from the off setting to the high speed
setting according to the weather conditions. The wipers
can be left in a rainsense mode even when it is not
raining.
3-9

When the headlamps are turned on while the vehicle is
on, the headlamps turn off automatically 10 minutes
after the ignition is turned off. When the headlamps are
turned on while the vehicle is off, the headlamps will
stay on for 10 minutes before automatically turning off to
prevent the battery from being drained. Turn the
headlamp control to off and then back to the headlamp
on position to make the headlamps stay on for an
additional 10 minutes.
Push the turn signal/multifunction lever toward the
instrument panel to change the headlamps from low
beam to high beam.
Headlamps on Reminder
If a door is open, a reminder chime will sound when the
headlamps or parking lamps are manually turned on
and the key is out of the ignition. To turn off the chime,
turn the headlamp switch to off or AUTO and then
back on, or close and re-open the door. In the AUTO
mode, the headlamps turn off once the ignition is
in LOCK/OFF or may remain on until the headlamp
delay ends (if enabled in the DIC). See “Exit Lighting”
underDIC Vehicle Customization (With DIC Buttons) on
page 3-67.
Daytime Running Lamps (DRL)
Daytime Running Lamps (DRL) can make it easier for
others to see the front of your vehicle during the
day. Fully functional daytime running lamps are required
on all vehicles rst sold in Canada.
The DRL system will come on when the following
conditions are met:
The ignition is on.
The exterior lamps control is in AUTO.
The transmission is not in P (Park).
The light sensor determines it is daytime.
When the DRL are on, only the DRL lamps will be on.
The taillamps, sidemarker, instrument panel lights,
and other lamps will not be on.
When it begins to get dark, the automatic headlamp
system will switch from DRL to the headlamps.
To turn off the DRL lamps, turn the exterior lamps
control to the OFF position and then release. For
vehicles rst sold in Canada, the transmission must be
in the P (Park) position, before the DRL lamps can
be turned off.
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