2008 GMC ENVOY heater

If a child restraint has been installed and the on
indicator is lit, turn the vehicle off. Remove the child
restraint from the vehicle and reinstall the child restraint.
If, after reinstalling the child restraint and restarting
the vehicle, the on indicator is still lit, check to make
sure that the vehicle’s seatback is not pressing the child
restraint into the seat cushion. If this happens, slightly
recline the vehicle’s seatback and adjust the seat
cushion if possible. Also make sure the child restraint
is not trapped under the vehicle head restraint.
If this happens, adjust the head restraint.
Remove any additional material from the seat such as
blankets, cushions, seat covers, seat heaters or seat
massagers before reinstalling or securing the child
restraint.
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.
To remove the child restraint, unbuckle the vehicle’s
safety belt and let it go back all the way.Airbag System
Your vehicle has the following airbags:
A frontal airbag for the driver.
A frontal airbag for the right front passenger.
A roof-rail airbag for the driver and the passenger
seated directly behind the driver.
A roof-rail airbag for the right front passenger and
the passenger seated directly behind the right
front passenger.
All of the airbags in your vehicle will have the word
AIRBAG embossed in the trim or on an attached label
near the deployment opening.
For frontal airbags, the word AIRBAG will appear on
the middle part of the steering wheel for the driver and
on the instrument panel for the right front passenger.
With roof-rail airbags, the word AIRBAG will appear
along the headliner or trim.
Airbags are designed to supplement the protection
provided by safety belts. Even though today’s airbags
are also designed to help reduce the risk of injury
from the force of an inating bag, all airbags must
inate very quickly to do their job.
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The passenger sensing system is designed to turn off
the right front passenger’s 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’s 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.If a child restraint has been installed and the on indicator
is lit, turn the vehicle off. Remove the child restraint from
the vehicle and reinstall the child restraint following the
child restraint manufacturer’s directions and refer to
Securing a Child Restraint in the Right Front Seat
Position on page 1-50.
If, after reinstalling the child restraint and restarting the
vehicle, the on indicator is still lit, check to make sure that
the vehicle’s seatback is not pressing the child restraint
into the seat cushion. If this happens, slightly recline
the vehicle’s seatback and adjust the seat cushion if
possible. 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 1-10.
Remove any additional material from the seat such as
blankets, cushions, seat covers, seat heaters or seat
massagers before reinstalling or securing the child
restraint.
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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The passenger sensing system is designed to enable
(may inate) the right front passenger’s frontal
airbag anytime the system senses that a person of adult
size is sitting properly in the right front passenger’s
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’s frontal
airbag, depending upon the person’s seating posture
and body build. Everyone in your vehicle who has
outgrown child restraints should wear a safety belt
properly — whether or not there is an airbag for that
person.
If a person of adult-size is sitting in the right front
passenger’s seat, but the off indicator is lit, it could be
because that person is not sitting properly in the seat.
If this happens, turn the vehicle off, remove any additional
material from the seat, such as blankets, cushions, seat
covers, seat heaters or seat massagers and ask the
person to place the seatback in the fully upright position,
then sit upright in the seat, centered on the seat cushion,
with the person’s legs comfortably extended. Restart the
vehicle and have the person remain in this position for
two to three minutes. This will allow the system to detect
that person and then enable the right front passenger’s
frontal airbag.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.
If you ever pull the shoulder portion of the belt out all the
way, you will engage the child restraint locking feature.
This may unintentionally cause the passenger sensing
system to turn the airbag(s) off for some adult size
occupants. If this happens, just let the belt go back
all the way and start again.
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{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 3-33for 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. We recommend
that you not use seat covers or other aftermarket
equipment other than any that GM has approved for
your specic vehicle. SeeAdding Equipment to Your
Airbag-Equipped Vehicle on page 1-66for more
information about modications 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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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 1-61.
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 5-76
for 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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Keys...............................................................2-3
Remote Keyless Entry (RKE) System................2-4
Remote Keyless Entry (RKE) System
Operation...................................................2-5
Doors and Locks.............................................2-7
Door Locks....................................................2-7
Power Door Locks..........................................2-8
Delayed Locking.............................................2-8
Programmable Automatic Door Locks................2-9
Rear Door Security Locks..............................2-11
Lockout Protection........................................2-11
Liftgate/Liftglass............................................2-12
Windows........................................................2-13
Power Windows............................................2-14
Sun Visors...................................................2-15
Theft-Deterrent Systems..................................2-16
Content Theft-Deterrent.................................2-16
Passlock
®(U. S. Only)..................................2-17
PASS-Key®III+............................................2-18
PASS-Key®III+ Operation (Canada Only).........2-18
Starting and Operating Your Vehicle................2-20
New Vehicle Break-In....................................2-20
Ignition Positions..........................................2-21Retained Accessory Power (RAP)...................2-22
Starting the Engine.......................................2-22
Adjustable Throttle and Brake Pedal................2-24
Engine Coolant Heater..................................2-24
Active Fuel Management™.............................2-25
Automatic Transmission Operation...................2-26
Four-Wheel Drive..........................................2-29
Parking Brake..............................................2-33
Shifting Into PARK (P)...................................2-34
Shifting Out of PARK (P)...............................2-36
Parking Over Things That Burn.......................2-37
Engine Exhaust............................................2-37
Running the Vehicle While Parked..................2-38
Mirrors...........................................................2-39
Manual Rearview Mirror.................................2-39
Manual Rearview Mirror with OnStar
®..............2-39
Automatic Dimming Rearview Mirror with
OnStar
®and Compass...............................2-39
Automatic Dimming Rearview Mirror with
OnStar
®, Compass and Temperature
Display....................................................2-41
Automatic Dimming Rearview Mirror with
Compass and Temperature Display..............2-44
Section 2 Features and Controls
2-1

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 closer for better pedal reach.
The vehicle must be in PARK (P) for this feature to
operate.
The switch used to adjust
the pedals is located on
the steering column.
Press the switch forward or backward to move the
pedals closer or farther away from you.
Engine Coolant Heater
The engine coolant heater, if available, can help in cold
weather conditions at or below 0°F (−18°C) for easier
starting and better fuel economy during engine warm-up.
Plug in the coolant heater at least four hours before
starting your vehicle. An internal thermostat in the
plug-end of the cord may exist which will prevent
engine coolant heater operation at temperatures
above 0°F (−18°C).
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.
The cord is located on the driver’s side of the
engine compartment next to the battery box
facing the engine.
3. Plug it into a normal, grounded 110-Volt AC outlet.
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{CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the
wrong kind of extension cord could overheat
and cause a re. You could be seriously
injured. Plug the cord into a properly grounded
three-prong 110-volt AC outlet. If the cord will
not reach, use a heavy-duty three-prong
extension cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and
store the cord as it was before to keep it away
from moving engine parts. If you do not, it could
be damaged.
How long should you keep the coolant heater plugged in?
The answer depends on the outside temperature, the
kind of oil you have, and some other things. Instead of
trying to list everything here, we ask that you contact your
dealer in the area where you will be parking your vehicle.
The dealer/retailer can give you the best advice for that
particular area.
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 your 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.
2-25