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See “Safety Belts” and “Child Restraints” in the
Index for additional information about the
importance of proper restraint use.
{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 airbag(s). SeeAirbag
Readiness Light on page 250for more on
this, including important safety
information.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. You may want to consider not
using seat covers or other aftermarket equipment.
SeeAdding Equipment to Your Airbag-Equipped
Vehicle on page 102for more information
about modi cations 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.
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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 644.
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 in ation.
Q:Because I have a disability, I have to get
my vehicle modi ed. 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, rollover sensor
module, steering wheel, instrument panel,
overhead console, ceiling headliner, ceiling
and pillar garnish trim, roof-mounted rollover
airbag modules, or airbag wiring 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 644.
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Restraint System Check
Checking the 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. Keep safety belts clean and dry.
SeeCare of Safety Belts on page 601for more
information.
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.
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 roof-mounted rollover airbags (if equipped).
Do not open or break the airbag coverings.
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Automatic Dimming Rearview Mirror with
Compass and Temperature Display........ 173
Outside Manual Mirrors............................. 174
Outside Trailer-Tow Mirrors....................... 175
Outside Power Mirrors............................... 176
Outside Power Foldaway Mirrors............... 177
OnStar
®System.......................................... 180
Universal Home Remote System................ 184
System Identi cation.................................. 184
Universal Home Remote System............... 185
Universal Home Remote System Operation
(With One Triangular LED)...................... 185
Universal Home Remote System
Operation (With Three Round LED)....... 189Storage Areas............................................. 196
Glove Box................................................. 196
Cupholder(s).............................................. 196
Instrument Panel Storage Area.................. 197
Center Console Storage Area.................... 197
Luggage Carrier........................................ 198
Rear Seat Armrest.................................... 199
Cargo Management System...................... 199
Sunroof....................................................... 200
Section 2 Features and Controls
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PASS-Key®III+ Operation
Your vehicle has PASS-Key®III+ (Personalized
Automotive Security System) theft-deterrent
system. PASS-Key
®III+ is a passive theft-deterrent
system. This means you do not have to do anything
special to arm or disarm the system. It works when
you transition the key to RUN, ACCESSORY or
START from the OFF position.
When the PASS-Key
®III+ system senses that
someone is using the wrong key, it prevents the
vehicle from starting. Anyone using a
trial-and-error method to start the vehicle will be
discouraged because of the high number of
electrical key codes.
If the engine does not start and the security light
on the instrument panel cluster comes on
when trying to start the vehicle, the key may have
a damaged transponder. Turn the ignition off
and try again.If the engine still does not start, and the key
appears to be undamaged, try another ignition
key. At this time, you may also want to check the
fuse, seeFuses and Circuit Breakers on
page 608. If the engine still does not start with the
other key, your vehicle needs service. If your
vehicle does start, the rst key may be faulty. See
your dealer who can service the PASS-Key
®III+
to have a new key made. In an emergency,
contact Roadside Assistance.
It is possible for the PASS-Key
®III+ decoder to
learn the transponder value of a new or
replacement key. Up to nine additional keys may
be programmed for the vehicle. The following
procedure is for programming additional keys only.
If all the currently programmed keys are lost or
do not operate, you must see your dealer or
a locksmith who can service PASS-Key
®III+ to
have keys made and programmed to the system.
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Adjustable Throttle and Brake Pedal
If your vehicle has this feature, you can change
the position of the throttle and brake pedals.
This feature is designed for shorter drivers, since
the pedals cannot move farther away from the
standard position, but can move toward the driver
for better pedal reach.
The switch used to
adjust the pedals is
located on the
instrument panel below
the climate control
system.
Press the arrow at the bottom of the switch to
move the pedals closer to your body. Press
the arrow at the top of the switch to move the
pedals away from your body.Before you start driving, fully press the brake
pedal to con rm the adjustment is right for you.
While driving, make only small adjustments.
No adjustment to the pedals can be made when
the vehicle is in REVERSE (R) or while using
the cruise control.
Your vehicle may have a memory function which
allows pedal settings to be saved and recalled.
SeeMemory Seat, Mirrors, and Pedals on page 13
for more information.
Engine Coolant Heater
Your vehicle may have an engine coolant heater.
If your vehicle has the DURAMAX
®Diesel
engine, see the DURAMAX®Diesel manual for
more information.
In very cold weather, 0°F (−18°C) or colder, the
engine coolant heater can help. You will get easier
starting and better fuel economy during engine
warm-up.
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Active Fuel Management™
Your vehicle’s V8 engine may have Active Fuel
Management™. This system allows the engine to
operate on either all or half of its cylinders,
depending on the driving conditions.
When less power is required, such as cruising at a
constant vehicle speed, the system will operate
in the half cylinder mode, allowing your vehicle to
achieve better fuel economy. When greater
power demands are required, such as accelerating
from a stop, passing, or merging onto a freeway,
the system will maintain full-cylinder operation.
Your vehicle has an Active Fuel Management™
indicator. For more information on using this
display seeDIC Operation and Displays (With DIC
Buttons) on page 268orDIC Operation and
Displays (Without DIC Buttons) on page 275.
Automatic Transmission Operation
If your vehicle is has an automatic transmission,
it has an electronic shift position indicator
within the instrument panel cluster. This display
comes on when the ignition key is turned to
the RUN position.There are several different positions for the
shift lever.
See “Range Selection Mode” later in this section.
PARK (P):This position locks your rear wheels. It
is the best position to use when you start the engine
because your vehicle cannot move easily.
Hydra-Matic®4-Speed Automatic Transmission
Allison Transmission®or Hydra-Matic®6-Speed
Automatic Transmission
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The tow/haul mode adjusts the transmission shift
pattern to reduce shift cycling, providing
increased performance, vehicle control, and
transmission cooling when towing or hauling
heavy loads.
The selector button is located on the end of
the shift lever. Turn the tow/haul on and off by
pressing the button. When the tow/haul is on, a
light on the instrument panel cluster will come on.
SeeTow/Haul Mode Light on page 266for more
information.
Also see Tow Haul Mode underTowing a Trailer
on page 445for more information.Tow/Haul Mode (Allison Transmission®
or Hydra-Matic®6-Speed Automatic
Transmission)
If your vehicle has an Allison or Hydra-Matic®
6-speed automatic transmission®, it has a tow/haul
mode. The tow/haul mode adjusts the transmission
shift pattern to reduce shift cycling, providing
increased performance, vehicle control, and
transmission cooling when towing or hauling
heavy loads.
145