lock GMC YUKON XL 2018 Manual Online

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
Driving and Operating 213Warning (Continued)And, if you leave the vehicle with
the engine running, it could
overheat and even catch fire. You
or others could be injured. Do not
leave the vehicle with the engine
running unless you have to.
If you have to leave the vehicle with
the engine running, be sure the
vehicle is in P (Park) and the
parking brake is firmly set before
you leave it. After you move the shift
lever into P (Park), hold the regular
brake pedal down. Then, see if you
can move the shift lever away from
P (Park) without first pulling it toward
you. If you can, it means that the
shift lever was not fully locked into
P (Park).
Torque Lock
If you are parking on a hill and you
do not shift the transmission into
P (Park) properly, the weight of the
vehicle may put too much force on
the parking pawl in the
transmission. You may find it difficult to pull the shift lever out of P (Park).
This is called torque lock. To
prevent torque lock, set the parking
brake and then shift into P (Park)
properly before you leave the
driver seat.
When you are ready to drive, move
the shift lever out of P (Park) before
you release the parking brake.
If torque lock does occur, you may
need to have another vehicle push
yours a little uphill to take some of
the pressure from the parking pawl
in the transmission. You will then be
able to pull the shift lever out of
P (Park).
Shifting out of Park This vehicle is equipped with an
electronic shift lock release system.
The shift lock release system is
designed to prevent movement of
the shift lever out of P (Park), unless
the ignition is on and the 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 the vehicle has an uncharged
battery or a battery with low voltage,
try charging or jump starting the
battery. See Jump Starting - North
America 0 351 .
To shift out of P (Park):
1. Apply the brake pedal.
2. Move the shift lever to the
desired position.
If you still are unable to shift out of
P (Park):
1. Ease the pressure on the shift
lever.
2. While holding down the brake
pedal, push the shift lever all
the way into P (Park).
3. Move the shift lever to the
desired position.
If you are still having a problem
shifting, then have the vehicle
serviced soon.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
Driving and Operating 215
Engine Exhaust
{ WarningEngine exhaust contains carbon
monoxide (CO), which cannot be
seen or smelled. Exposure to CO
can cause unconsciousness and
even death.
Exhaust may enter the vehicle if:
.
The vehicle idles in areas
with poor ventilation
(parking garages, tunnels,
deep snow that may block
underbody airflow or tail
pipes).
.
The exhaust smells or
sounds strange or different.
.
The exhaust system leaks
due to corrosion or damage.
.
The vehicle exhaust system
has been modified,
damaged, or improperly
repaired.
(Continued) Warning (Continued) .
There are holes or openings
in the vehicle body from
damage or aftermarket
modifications that are not
completely sealed.
If unusual fumes are detected or
if it is suspected that exhaust is
coming into the vehicle:
.
Drive it only with the
windows completely down.
.
Have the vehicle repaired
immediately.
Never park the vehicle with the
engine running in an enclosed
area such as a garage or a
building that has no fresh air
ventilation. Running the Vehicle
While Parked It is better not to park with the
engine running.
If the vehicle is left with the engine
running, follow the proper steps to
be sure the vehicle will not move.
See Shifting Into Park 0 212 and
Engine Exhaust 0 215 .
If parking on a hill and pulling a
trailer, see Driving Characteristics
and Towing Tips 0 259 .

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
216 Driving and Operating
Automatic
Transmission If equipped, there is an electronic
shift lever position indicator within
the instrument cluster. This display
comes on when the ignition is
turned on.
There are several different positions
for the shift lever.
See “ Range Selection Mode ” under
Manual Mode 0 218 .
P : This position locks the drive
wheels. Use P (Park) when starting
the engine because the vehicle
cannot move easily. When parked
on a hill, especially when the
vehicle has a heavy load, you might
notice an increase in the effort to
shift out of P (Park). See “ Torque
Lock ” under Shifting Into Park
0 212 . { WarningIt is dangerous to get out of the
vehicle if the shift lever is not fully
in P (Park) with the parking brake
firmly set. The vehicle can roll.
Do not leave the vehicle when the
engine is running. If you have left
the engine running, the vehicle
can move suddenly. You or others
could be injured. To be sure the
vehicle will not move, even when
you are on fairly level ground,
always set the parking brake and
move the shift lever to P (Park).
See Shifting Into Park 0 212 and
Driving Characteristics and
Towing Tips 0 259 .
{ Warning
If you have four-wheel drive, the
vehicle will be free to roll — even
if the shift lever is in P (Park) — if
the transfer case is in N (Neutral).
(Continued) Warning (Continued) So, be sure the transfer case is in
a drive gear, Two-Wheel Drive
High or Four-Wheel Drive High or
Four-Wheel Drive Low — not in
N (Neutral). See Shifting Into Park
0 212 .
R : Use this gear to back up.
CautionShifting to R (Reverse) while the
vehicle is moving forward could
damage the transmission. The
repairs would not be covered by
the vehicle warranty. Shift to
R (Reverse) only after the vehicle
is stopped.
To rock the vehicle back and forth to
get out of snow, ice, or sand without
damaging the transmission, see If
the Vehicle Is Stuck 0 200 .

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
Driving and Operating 225Shifting Out of 4
nTo shift:
1. The vehicle must be stopped or
moving less than 5 km/h
(3 mph) with the transmission
in N (Neutral) and the ignition
on. It is best for the vehicle to
be moving
1.6 to 3.2 km/h (1 to 2 mph).
2. Turn the knob to 4
m , AUTO,
or 2
m . Wait for the 4
m , AUTO,
or 2
m indicator light to stop
flashing before shifting the
transmission into gear.
Caution
Shifting the transmission into gear
before the requested mode
indicator light has stopped
flashing could damage the
transfer case.
If the transmission is in gear and/or
moving more than 5 km/h (3 mph),
the 4
m , AUTO, or 2
m indicator light
will flash for 30 seconds but will not complete the shift. With the vehicle
moving less than 5 km/h (3 mph),
and the transmission in N (Neutral),
attempt the shift again.
Shifting Into N (Neutral)
To shift into N (Neutral):
1. Park the vehicle on a level
surface.
2. Set the parking brake and
press and hold the brake
pedal. See Parking Brake
0 228 .
3. Start the vehicle or turn the
ignition on.
4. Shift the transmission to
N (Neutral).
5. Shift the transfer case to 2
m .
6. Turn the transfer case knob
clockwise to N (Neutral) until it
stops and hold it there until the
N (Neutral) light starts blinking.
This will take at least
10 seconds. Then slowly
release the knob to the 4
nposition. The N (Neutral) light will come on when the transfer
case shift to N (Neutral) is
complete.
7. With the engine running, verify
that the transfer case is in
N (Neutral) by shifting the
transmission to R (Reverse),
then shift the transmission to
D (Drive). There should be no
movement of the vehicle while
shifting the transmission.
8. Turn the engine off, and the
ignition to ACC/ACCESSORY.
9. Place the transmission shift
lever in P (Park). See
Recreational Vehicle Towing
0 355 .
10. Turn the ignition off.
Shifting Out of N (Neutral)
To shift out of N (Neutral):
1. Set the parking brake and
apply the brake pedal.
2. Turn the ignition on with the
engine off.
3. Shift the transmission to
N (Neutral).

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
Driving and Operating 227Shifting Into 4
m or AUTO
Turn the knob to the 4
m or AUTO
position. This can be done at any
speed. The indicator light will flash
while shifting. It will remain on when
the shift is completed.
Shifting Into 2
mTurn the knob to the 2
m position.
This can be done at any speed. The
indicator light will flash while
shifting. It will remain on when the
shift is completed. Brakes Antilock Brake
System (ABS) This vehicle has an Antilock Brake
System (ABS), an advanced
electronic braking system that helps
prevent a braking skid.
When the vehicle begins to drive
away, ABS checks itself.
A momentary motor or clicking noise
may be heard while this test is going
on, and it may even be noticed that
the brake pedal moves a little. This
is normal.
If there is a problem with ABS, this
warning light stays on. See Antilock
Brake System (ABS) Warning Light
0 145 . If driving safely on a wet road and it
becomes necessary to slam on the
brakes and continue braking to
avoid a sudden obstacle, a
computer senses the wheels are
slowing down. If one of the wheels
is about to stop rolling, the computer
will separately work the brakes at
each wheel.
ABS can change the brake pressure
to each wheel, as required, faster
than any driver could. This can help
you steer around the obstacle while
braking hard.
As the brakes are applied, the
computer keeps receiving updates
on wheel speed and controls
braking pressure accordingly.
Remember: ABS does not change
the time needed to get a foot up to
the brake pedal or always decrease
stopping distance. If you get too
close to the vehicle in front of you,
there will not be enough time to
apply the brakes if that vehicle
suddenly slows or stops. Always
leave enough room up ahead to
stop, even with ABS.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
232 Driving and Operating Noise from the hydraulic brake
control module is normal when HDC
is active.
When HDC is activated, the initial
HDC speed is set to the current
driving speed. It can be increased or
decreased by pressing +RES or
SET- on the steering wheel, or by
applying the accelerator or brake
pedal. This adjusted speed
becomes the new set speed.
HDC will remain enabled between
30 and 60 km/h (19 and 37 mph);
however, vehicle speed cannot be
set or maintained in this range. HDC
will automatically disable if the
vehicle speed is above 80 km/h
(50 mph) or above 60 km/h
(37 mph) for at least 30 seconds.
5 must be pressed again to
re-enable HDC. HDC may disable
after an extended period of use.
If this happens, HDC will require
time to cool down. The length of
time HDC remains active depends
on road conditions, grade, set
speed, vehicle loading, and outside
temperature. When enabled, if the vehicle speed
is above 30 km/h (19 mph) and
below 60 km/h (37 mph), a DIC
message will display.
Magnetic Ride Control This vehicle may have a semi-active
damping system called Magnetic
Ride Control. With this feature,
improved vehicle ride and handling
is provided under a variety of
passenger and loading conditions.
Magnetic Ride Control is fully
automatic and uses a computer
controller to continuously monitor
vehicle speed, wheel to body
position, lift/dive, and steering
position of the vehicle. The
controller then sends signals to
each shock absorber to
independently adjust the damping
level to provide the optimum
vehicle ride.
Magnetic Ride Control also interacts
with the Tow/Haul Mode that, when
activated, will provide additional
control of the shock absorbers. This
additional control results in better
ride and handling characteristics when the vehicle is loaded or towing
a trailer. See “ Tow/Haul Mode ”
under Towing Equipment 0 267 .
Locking Rear Axle Vehicles with a locking rear axle can
give more traction on snow, mud,
ice, sand, or gravel. It works like a
standard axle most of the time, but
when traction is low, this feature will
allow the rear wheel with the most
traction to move the vehicle.
Automatic Level Control The Automatic Level Control (ALC)
rear suspension is available on
light-duty vehicles and comes as a
part of the Magnetic Ride Control
suspension, if equipped. ALC may
also be available as a stand alone
feature.
This type of level control is fully
automatic and will provide a better
leveled riding position as well as
better handling under a variety of
passenger and loading conditions.
An air compressor connected to the
rear shocks will raise or lower the
rear of the vehicle to maintain

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
236 Driving and Operating If a vehicle is detected in your path,
ACC can speed up the vehicle or
apply limited, moderate braking to
maintain the selected following gap.
To disengage ACC, apply the brake.
If the Traction Control System (TCS)
or electronic stability control system
activates while ACC is engaged,
ACC may automatically disengage.
See Traction Control/Electronic
Stability Control 0 229 . When road
conditions allow ACC to be safely
used, the ACC can be turned
back on.
ACC will not engage if the TCS or
electronic stability control system is
disabled.
{ Warning
ACC has limited braking ability
and may not have time to slow
the vehicle down enough to avoid
a collision with another vehicle
you are following. This can occur
when vehicles suddenly slow or
stop ahead, or enter your lane.
Also see “ Alerting the Driver ” in
(Continued) Warning (Continued) this section. Complete attention is
always required while driving and
you should be ready to take
action and apply the brakes. See
Defensive Driving 0 190 .
{ WarningACC will not detect or brake for
children, pedestrians, animals,
or other objects.
Do not use ACC when:
.
On winding and hilly roads
or when the sensors are
blocked by snow, ice, or dirt.
The system may not detect
a vehicle ahead. Keep the
entire front of the vehicle
clean.
(Continued) Warning (Continued) .
Visibility is low, such as in
fog, rain, or snow
conditions. ACC
performance is limited under
these conditions.
.
On slippery roads where
fast changes in tire traction
can cause excessive
wheel slip.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
240 Driving and Operating braking may feel or sound different
than if the brakes were applied
manually. This is normal.
Stationary or Very Slow-Moving
Objects
{ WarningACC may not detect and react to
stopped or slow-moving vehicles
ahead of you. For example, the
system may not brake for a
vehicle it has never detected
moving. This can occur in
stop-and-go traffic or when a
vehicle suddenly appears due to
a vehicle ahead changing lanes.
Your vehicle may not stop and
could cause a crash. Use caution
when using ACC. Your complete
attention is always required while
driving and you should be ready
to take action and apply the
brakes. ACC Automatically Disengages
ACC may automatically disengage
and you will need to manually apply
the brakes to slow the vehicle if:
.
Your vehicle speed goes below
the minimum speed of 16 km/h
(10 mph).
.
The sensors are blocked.
.
The Traction Control System
(TCS) or electronic stability
control system has activated or
been disabled.
.
There is a fault in the system.
.
The radar falsely reports a
blockage when driving in a
desert or remote area with no
other vehicles or roadside
objects. A DIC message may
display to indicate that ACC is
temporarily unavailable.
A message will appear on the DIC
indicating that cruise is disengaging.
The ACC indicator will turn white
when ACC is no longer active. ACC Override
If using the accelerator pedal while
ACC is active, a warning message
in the DIC and in the HUD,
if equipped, will indicate that
automatic braking will not occur.
See Vehicle Messages 0 157 . ACC
will resume operation when the
accelerator pedal is not being
pressed.
{ WarningThe ACC will not automatically
apply the brakes if your foot is
resting on the accelerator pedal.
You could crash into a vehicle
ahead of you.
Curves in the Road
{ Warning
On curves, ACC may not detect a
vehicle ahead in your lane. You
could be startled if the vehicle
accelerates up to the set speed,
(Continued)

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
242 Driving and Operating Do Not Use ACC on Hills and
When Towing a Trailer
Do not use ACC when driving on
steep hills or when towing a trailer.
ACC will not detect a vehicle in the
lane while driving on steep hills. The
driver will often need to take over
acceleration and braking on steep
hills, especially when towing a
trailer. If the brakes are applied, the
ACC disengages.
Disengaging ACC
There are three ways to
disengage ACC:
.
Step lightly on the brake pedal.
.
Press
* .
.
Press
5 . Erasing Speed Memory
The cruise control set speed is
erased from memory if
5 is pressed
or if the ignition is turned off.
Cleaning the Sensing System
The radar sensor on the front of the
vehicle can become blocked by
snow, ice, dirt, or mud. This area
needs to be cleaned for ACC to
operate properly.
For cleaning instructions, see
“ Washing the Vehicle ” under
Exterior Care 0 360 .
System operation may also be
limited under snow, heavy rain,
or road spray conditions. Driver Assistance
Systems This vehicle may have features that
work together to help avoid crashes
or reduce crash damage while
driving, backing, and parking. Read
this entire section before using
these systems.
{ WarningDo not rely on the Driver
Assistance Systems. These
systems do not replace the need
for paying attention and driving
safely. You may not hear or feel
alerts or warnings provided by
these systems. Failure to use
proper care when driving may
result in injury, death, or vehicle
damage. See Defensive Driving
0 190 .
(Continued)

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
244 Driving and Operating
1. View Displayed by the
Camera
1. View Displayed by the
Camera
2. Corners of the Rear Bumper Displayed images may be farther or
closer than they appear. The area
displayed is limited and objects that
are close to either corner of the
bumper or under the bumper do not
display.
A warning triangle may display to
show that RPA has detected an
object. This triangle changes from
amber to red and increases in size
the closer the object.
{ WarningThe camera(s) do not display
children, pedestrians, bicyclists,
crossing traffic, animals, or any
other object outside of the
cameras ’ field of view, below the
bumper, or under the vehicle.
Shown distances may be different
from actual distances. Do not
drive or park the vehicle using
only these camera(s). Always
check behind and around the
vehicle before driving. Failure to
use proper care may result in
injury, death, or vehicle damage. Parking Assist
With RPA, and if equipped with FPA,
as the vehicle moves at speeds of
less than 8 km/h (5 mph) the
sensors on the bumpers may detect
objects up to 2.5 m (8 ft) behind and
1.2 m (4 ft) in front of the vehicle
within a zone 25 cm (10 in) high off
the ground and below bumper level.
These detection distances may be
shorter during warmer or humid
weather. Blocked sensors will not
detect objects and can also cause
false detections. Keep the sensors
clean of mud, dirt, snow, ice, and
slush; and clean sensors after a car
wash in freezing temperatures.
{ Warning
The Parking Assist system does
not detect children, pedestrians,
bicyclists, animals, or objects
located below the bumper or that
are too close or too far from the
vehicle. It is not available at
speeds greater than 8 km/h
(5 mph). To prevent injury, death,
(Continued)