2008 GMC YUKON DENALI service

On vehicles with a liftglass, press the button on the
underside of the license pocket applique (A) to open it.
The liftglass can also be opened by pressing the
liftglass release button on the RKE.To open the entire liftgate, press the power liftgate
release button on the RKE or in the vehicle. SeePower
Liftgate on page 2-15. You can also press the
touchpad on the underside of the liftgate handle (B).
The liftgate will open after a slight delay. The vehicle
must be in PARK (P) to open the liftgate. To close the
liftgate, use the pull cup or pull strap as an aid.
The liftgate or liftglass cannot be opened if the rear
wipers are in motion. Attempting to open the liftgate or
liftglass while the rear wipers are in motion will cause
the release of the liftglass or liftgate to delay until
the wipers are parked off the liftglass.
Both the liftglass and liftgate have an electric latch.
If the battery is disconnected or has low voltage,
the liftglass and liftgate will not open. The liftglass and
liftgate will resume operation when the battery is
reconnected and charged.
If the battery is properly connected and has adequate
voltage, and the liftgate or liftglass still will not function,
your vehicle should be taken to a dealership for service.
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The power liftgate may be temporarily disabled under
extreme temperatures, or under low battery conditions.
If this occurs, the liftgate can still be operated
manually.
If you shift the transmission out of PARK (P) while the
power function is in progress, the liftgate power function
will continue to completion. If you shift the transmission
out of PARK (P) and accelerate before the power
liftgate latches closed, the liftgate may reverse to the
open position. Cargo could fall out of the vehicle. Always
make sure the power liftgate is closed and latched
before you drive away.
If you power open the liftgate and the liftgate support
struts have lost pressure, the lights will ash and a
chime will sound. The liftgate will stay open temporarily,
then slowly close. See your dealer/retailer for service
before using the liftgate.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.
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Manual Operation of Power Liftgate
To change the liftgate to manual operation, press the
switch on the center 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.
If the battery is properly connected with adequate
voltage, the switch is not disabled, and the liftgate still
will not function, your vehicle should be taken to a
dealer/retailer for service.
Power Running Boards
Your vehicle may have power running boards.
The power running boards automatically extend from
beneath the vehicle on the side in which the door
has been opened. Once the door is closed, the running
boards will automatically move back under the vehicle
after a brief delay. The vehicle must not be moving
for the running boards to extend or retract.
The switch used to disable
the power running boards
is located on the center
console below the climate
control system.
The running boards cannot be disabled in the extended
position.
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Testing the Alarm
To test the alarm:
1. From inside the vehicle, lower the driver’s window
and open the driver’s door.
2. Activate the system by locking the doors with the
power door lock switch while the door is open, or
with the RKE transmitter.
3. Get out of the vehicle, close the door and wait for
the security light to go out.
4. Then reach in through the window, unlock the door
with the manual door lock and open the door. This
should set off the alarm.
While the alarm is set, the power door unlock switch will
not work.
If the alarm does not sound when it should but the
headlamps ash, check to see if the horn works. The
horn fuse may be blown. To replace the fuse, seeFuses
and Circuit Breakers on page 5-108.
If the alarm does not sound or the headlamps do not
ash, the vehicle should be serviced by your
dealer/retailer.
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.
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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.
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, ACC/ACCESSORY or START
from the LOCK/OFF position.
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.
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, 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 5-108. 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
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 10 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/retailer
or a locksmith who can service PASS-Key
®III+ to have
keys made and programmed to the system.
See your dealer/retailer or a locksmith who can service
PASS-Key
®III+ to get a new key blank that is cut
exactly as the ignition key that operates the system.
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To program the new additional key:
1. Verify that the new key has a
1stamped on it.
2. Insert the original, already programmed, 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 new key to be programmed and turn it to
the ON/RUN position within ve seconds of turning
the ignition to the LOCK/OFF position in Step 3.
The security light will turn off once the key has been
programmed.
5. Repeat Steps 1 through 4 if additional keys are to
be programmed.
If you lose or damage your PASS-Key
®III+ key, see
your dealer/retailer or a locksmith who can service
PASS-Key
®III+ to have a new key made.
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 4-42for 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.
In order to shift out of PARK (P), ignition must be in the
ON/RUN or ACC/ACCESSORY and the regular brake
pedal must be applied.A (LOCK/OFF):This position locks the ignition and
transmission. It is a theft-deterrent feature. The key can
only be removed when the ignition is turned to
LOCK/OFF.
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
it is, turn the steering wheel left and right while you
turn the key hard. If none of this works, then
your vehicle needs service.
B (ACC/ACCESSORY):This position lets things like
the radio and the windshield wipers operate while
the engine is off.
Lengthy operation of features such as the radio in the
ACC/ACCESSORY ignition position and the ON/RUN
position may drain the battery and prevent your vehicle
from starting. Do not operate your vehicle in the
ACC/ACCESSORY ignition position for a long period
of time.
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Torque Lock
If you are parking on a hill and you do not shift your
transmission into PARK (P) properly, the weight of the
vehicle can put too much force on the parking pawl in the
transmission. It might be difficult to pull the shift lever out
of PARK (P). This is called torque lock. To prevent torque
lock, set the parking brake and then shift into PARK (P)
properly before you leave the driver’s seat. To nd out
how, seeShifting Into PARK (P) on page 2-36.
When you are ready to drive, move the shift lever out of
PARK (P) before releasing the parking brake.
If torque lock does occur, you might need to have another
vehicle push yours a little uphill to take some of the
pressure from the parking pawl in the transmission. Then
you should be able to pull the shift lever out of PARK (P).
Shifting Out of PARK (P)
This vehicle is equipped with 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 or
ACC/ACCESSORY 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 5-40for more
information.
To shift out of PARK (P) use the following:
1. Apply the brake pedal.
2. Move the shift lever to the desired position.
If you still are unable to shift out of PARK (P):
1. Ease the pressure on the shift lever.
2. While holding down the brake pedal, press the shift
lever all the way into PARK (P).
3. Move the shift lever to the desired position.
If you are still having a problem shifting, then have your
vehicle serviced soon.
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