2008 GMC ENVOY DENALI service

PASS-Key®III+
The PASS-Key®III+ system operates on a radio
frequency subject to Federal Communications
Commission (FCC) Rules and with Industry Canada.
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation.
This device complies with RSS-210 of Industry Canada.
Operation is subject to the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modications to this system by other than
an authorized service facility could void authorization to
use this equipment.
PASS-Key
®III+ uses a radio frequency transponder in
the key that matches a decoder in your vehicle.
PASS-Key®III+ Operation
(Canada Only)
Your vehicle has a passive theft-deterrent system.
The system is automatically armed when the key
is removed from the ignition.
The system is automatically disarmed when the key is
turned to ON/RUN.
You do not have to manually arm or disarm the system.
The security light will come on if there is a problem
with arming or disarming the theft-deterrent system.
The key uses a transponder that matches an immobilizer
control unit in your vehicle. Only the correct key will
start the vehicle. If the key is ever damaged, you may
not be able to start your vehicle.
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When trying to start the vehicle, if the engine does not
start and the security light comes on, there may be
a problem with your theft-deterrent system. 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 5-110. 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/retailer who can service the
theft-deterrent system and have a new key made.
It is possible for the theft-deterrent system decoder to
learn the transponder value of a new or replacement
key. Up to 10 keys may be programmed for the vehicle.
The following procedure is for programming additional
keys only.Canadian Owners:If you lose or damage your keys,
only a dealer/retailer can service the theft-deterrent
system to have new keys made. To program additional
keys you will require two current driver’s keys.
To program a new key do the following:
1. Verify that the new key has PK3+ stamped on it.
2. Insert the current driver’s key in the ignition
and start the engine. If the engine will not start
see your dealer/retailer for service.
3. After the engine has started, turn the key to
LOCK/OFF, and remove the key.
4. Insert the second current driver’s key in the ignition
and start the engine within ten seconds of removing
the previous key. If the engine will not start see
your dealer/retailer for service.
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5. After the engine has started, turn the key to
LOCK/OFF, and remove the key. Insert the key
to be programmed and turn it to ON within
ten seconds of removing the previous key.
The security light will turn off once the key has
been programmed.
6. Repeat the Steps 1 through 5 if additional keys are
to be programmed.
If the security light comes on and stays on while driving,
you will be able to restart the engine if you turn it off.
The theft-deterrent system, however, is not working
properly and must be serviced by your dealer/retailer.
Your vehicle is not protected by the theft-deterrent
system at this time.
In an emergency, contact Roadside Assistance.
SeeRoadside Assistance Program on page 7-8.
Do not leave the key or device that disarms or
deactivates the theft deterrent system in the vehicle.Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice:Your vehicle does not need an elaborate
break-in. But it will perform better in the long run if
you follow these guidelines:
Keep your speed at 55 mph (88 km/h) or less for
the rst 500 miles (805 km).
Do not drive at any one constant speed, fast or
slow, for the rst 500 miles (805 km). Do not
make full-throttle starts. Avoid downshifting
to brake or slow the vehicle.
Avoid making hard stops for the rst 200 miles
(322 km) or so. During this time the new brake
linings are not yet broken in. Hard stops with new
linings can mean premature wear and earlier
replacement. Follow this breaking-in guideline
every time you get new brake linings.
Do not tow a trailer during break-in. SeeTowing
a Trailer on page 4-45for the trailer towing
capabilities of your vehicle and more
information.
Following break-in, engine speed and load can be
gradually increased.
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Ignition Positions
Use the key to turn the
ignition switch to four
different positions.
Press the regular brake pedal, and turn the ignition
to ON/RUN to shift out of PARK (P).
Notice:Using a tool to force the key from the
ignition switch could cause damage or break the
key. Use the correct key and turn the key only
with your hand. Make sure the key is all the way in.
If none of this works, then your vehicle needs
service.A (LOCK/OFF):This position locks the ignition and
transmission. It is a theft-deterrent feature. You will only
be able to remove the key when the ignition is turned
to LOCK/OFF.
If the steering wheel is locked, move it from right to left
and turn the key to ACC/ACCESSORY. If none of
this works, then your vehicle needs service.
B (ACC/ACCESSORY):This position lets you use
things like the radio and the windshield wipers when
the engine is off.
Lengthy operation of features such as the radio in the
ACC/ACCESSORY may drain the battery and prevent
your vehicle from starting. Do not operate your vehicle
in the ACC/ACCESSORY for a long period of time.
C (ON/RUN):This is the position for driving.
The battery could be drained if you leave the key in
the ACC/ACCESSORY or ON/RUN position with the
engine off. You may not be able to start your vehicle if the
battery is allowed to drain for an extended period of time.
D (START):This position starts the engine.
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AUTO (Automatic Four-Wheel Drive):This setting is
ideal for use when road conditions are variable. When
driving your vehicle in automatic four-wheel drive, the
front axle is engaged, but the vehicle’s power is sent to
the rear wheels. When the vehicle senses a loss of
traction, the system will automatically engage four-wheel
drive. Driving in this mode results in slightly lower fuel
economy than Two-Wheel High.
4
m(Four-Wheel High):This setting should be used
when you need extra traction, such as on snowy or
icy roads or in most off-road situations. This setting also
engages your front axle to help drive your vehicle.
4
n(Four-Wheel Low):This setting also engages
your front axle and delivers extra torque. It sends
maximum power to all four wheels. You might choose
this setting if you are driving off-road in deep sand,
deep mud, and climbing or descending steep hills.
{CAUTION:
Shifting the transfer case to NEUTRAL
can cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be seriously injured. Be sure to set
the parking brake before placing the transfer
case in NEUTRAL. SeeParking Brake on
page 2-33.
NEUTRAL:Shift the vehicle’s transfer case
to NEUTRAL only when towing your vehicle.
SeeRecreational Vehicle Towing on page 4-40
for more information.
An indicator light in the knob will show you which
position the transfer case is in. The indicator lights will
come on briey when you turn on the ignition and one will
stay on. If the lights do not come on, you should take your
vehicle to your dealer for service. An indicator light will
ash while shifting the transfer case. It will stay on when
the shift is complete. If for some reason the transfer case
cannot make a requested shift, it will return to the last
chosen setting.
If the service Four-Wheel Drive Warning Light on the
instrument panel cluster stays on, you should take
your vehicle to your dealer for service. SeeService
Four-Wheel Drive Warning Light on page 3-47for
further information.
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Shifting Out of PARK (P)
This vehicle has an electronic shift lock release system.
The shift lock release is designed to:
Prevent ignition key removal unless the shift lever
is in PARK (P) with the shift lever button fully
released, and
Prevent movement of the shift lever out of
PARK (P), unless the ignition is in ON/RUN
and the regular brake pedal is applied.
The shift lock release is always functional except in the
case of an uncharged or low voltage (less than 9 volt)
battery.If your vehicle has an uncharged battery or a battery
with low voltage, try charging or jump starting the
battery. SeeJump Starting on page 5-42for more
information.
To shift out of PARK (P) use the following:
1. Apply the brake pedal.
2. Press the shift lever button.
3. Move the shift lever to the desired position.
If you still are unable to shift out of PARK (P):
1. Fully release the shift lever button.
2. Hold the brake pedal down and press the shift lever
button again.
3. Move the shift lever to the desired position.
If you still cannot move the shift lever from PARK (P),
consult your dealer/retailer or a professional towing
service.
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{CAUTION:
If your vehicle has four-wheel drive, it will
be free to roll — even if the shift lever is in
PARK (P) — if the transfer case is in
NEUTRAL. So be sure the transfer case
is in a drive gear — not in NEUTRAL.
SeeFour-Wheel Drive on page 2-29.
Follow the proper steps to be sure your vehicle will not
move. SeeShifting Into PARK (P) on page 2-34.
If you are pulling a trailer, seeTowing a Trailer on
page 4-45.
Mirrors
Manual Rearview Mirror
When you are sitting in a comfortable driving position,
adjust the mirror so you can see clearly behind your
vehicle. Grip the mirror in the center to move it up
or down and side to side. The day/night adjustment
allows you to adjust the mirror to avoid glare from the
lamps behind you. Move the lever to the right for
nighttime use and to the left for daytime use.
Manual Rearview Mirror with
OnStar
®
When you are sitting in a comfortable driving position,
adjust the mirror so you can see clearly behind your
vehicle. Hold the mirror in the center to move it up or
down and side to side. The day/night adjustment allows
you to adjust the mirror to avoid glare from the lamps
behind you. Move the lever to the right for nighttime
use and to the left for daytime use.
There may also be three OnStar
®buttons located at the
bottom of the mirror face. See your dealer/retailer for
more information on the system and how to subscribe to
OnStar
®. SeeOnStar®System on page 2-48for more
information on the services OnStar®provides.
Automatic Dimming Rearview Mirror
with OnStar
®and Compass
Your vehicle may have an automatic-dimming rearview
mirror with a compass.
There may be three additional buttons for the OnStar
®
system. See your dealer/retailer for more information
on the system and how to subscribe to OnStar®.
SeeOnStar®System on page 2-48for more information
about the services OnStar®provides.
O(On/Off):This is the on/off button.
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Outside Convex Mirror
{CAUTION:
A convex mirror can make things (like other
vehicles) look farther away than they really are.
If you cut too sharply into the right lane, you
could hit a vehicle on your right. Check your
inside mirror or glance over your shoulder
before changing lanes.
The passenger side mirror is convex. A convex mirror’s
surface is curved so more can be seen from the
driver seat. It also makes things, like other vehicles,
look farther away than they really are.
Outside Heated Mirrors
Your vehicle may have this feature. When you operate
the rear window defogger, the defogger also warms the
heated driver’s and passenger’s outside rearview mirrors
to help clear them of ice, snow and condensation.
OnStar®System
OnStar uses several innovative technologies and live
advisors to provide you with a wide range of safety,
security, information, and convenience services. If your
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 you lock your keys in the vehicle, call OnStar at
1-888-4-ONSTAR and they can send a signal to unlock
your doors. If you need roadside assistance, press
the OnStar button and they can contact Roadside
Service for you.
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