2008 CHEVROLET TAHOE sensor

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 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.
Your vehicle may or may not have roof-rail airbags.
SeeAirbag System on page 1-76. 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.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.
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.
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The passenger sensing system will turn off the right
front passenger’s frontal airbag under certain conditions.
The driver’s airbags are not part of the passenger
sensing system.
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
right front 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.
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
it 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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Servicing Your Airbag-Equipped
Vehicle
Airbags affect how your vehicle should be serviced.
There are parts of the airbag system in several places
around your vehicle. Your dealer/retailer 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 7-16.
{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.
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 your 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, your vehicle has a passenger sensing
system for the right front passenger’s 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
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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). SeePassenger
Sensing System on page 1-85.
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.
If your vehicle has rollover roof-rail airbags, see
Different Size Tires and Wheels on page 5-84
for additional important information.Q:What if I added a snow plow? Will it keep
the airbags from working properly?
A:We have designed our airbag systems to work
properly under a wide range of conditions, including
snow plowing with vehicles that have the optional
Snow Plow Prep Package (RPO VYU). But do
not change or defeat the snow plow’s “tripping
mechanism.” If you do, it can damage your snow
plow and your vehicle, and it may cause an
airbag ination.
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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Obstacle Detection Features
If the liftgate encounters an obstacle during a power
open or close cycle, a warning chime will sound and the
liftgate will automatically reverse direction to the full
closed or open position. After removing the obstruction,
the power liftgate operation can be used again. If the
liftgate encounters multiple obstacles on the same power
cycle, the power function will deactivate, and you
must manually open or close the liftgate. The REAR
ACCESS OPEN warning message in the Driver
Information Center (DIC) will indicate that the liftgate is
open. After removing the obstructions, manually
open the liftgate to the full open position or close the
liftgate to the fully closed and latched position. The
liftgate will now resume normal power operation.
Your vehicle has pinch sensors located on the side
edges of the liftgate. If an object is caught between the
liftgate and the body and presses against this sensor,
the liftgate will reverse direction and open fully.
The liftgate will remain open until it is activated again or
closed manually. Do not force the liftgate open or
closed during a power cycle.
Manual Operation of Power Liftgate
To change the liftgate to manual operation, press the
switch on the overhead console to the OFF position.
With the power liftgate disabled and all of the doors
unlocked, the liftgate can be manually opened
and closed.
To open the liftgate, press the touchpad on the handle
on the outside of the liftgate, and lift the gate open.
To close the liftgate, use the pull cup to lower the liftgate
and close. The liftgate latch will power close. Always
close the liftgate before driving.
If the RKE button or the power close button on the
liftgate is pressed while power operation is disabled,
the lights will ash three times, but the liftgate will
not move.
It is not recommended that you drive with the liftgate
open, however, if you must drive with the liftgate open,
the liftgate should be set to manual operation by
pressing the OFF switch on the center console.
The liftgate has an electric latch. If the battery is
disconnected or has low voltage, the liftgate will not
open. The liftgate will resume operation when the battery
is reconnected and charged.
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Outside Heated Mirrors
The vehicle may have outside heated mirrors which
help clear them of condensation, snow, and ice.
<(Rear Window Defogger):Press to heat the
mirrors.
See “Rear Window Defogger” underDual Automatic
Climate Control System on page 3-24orClimate Control
System on page 3-22for 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 your vehicle before backing up. While
backing, be sure to look for objects and check
your vehicle’s mirrors.
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When the System Does Not Seem to
Work Properly
If the URPA system will not activate due to a temporary
condition, the message PARKING 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 parking brake pedal is depressed.
The ultrasonic sensors are not clean. Keep the
vehicle’s rear bumper free of mud, dirt, snow,
ice and slush. For cleaning instructions, see
Washing Your Vehicle on page 5-112.
A trailer was attached to the vehicle, or a bicycle or
an object was hanging out of the liftgate 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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The high-beam indicator on the instrument panel cluster
will come on. Release the lever to return to normal
operation.
Windshield Wipers
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 5-64.
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.
Turn the band with the wiper symbol to control the
windshield wipers.
8(Mist):Turn the band 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):To stop the wipers, move the band to 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):Turn the band away from you to
the rst solid band past the delay settings, for steady
wiping at low speed.
?(High Speed):Turn the band further, to the
second solid band past the delay settings, for
high-speed wiping.
Rainsense™ II Wipers
If your vehicle has 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 rainsensor.
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 rainsensor 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.
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