
Black plate (15,1)GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7576030) - 2015 - CRC - 8/18/14
Driving and Operating 9-15
In order to shift out of P (Park), the
ignition must be in ON/RUN or ACC/
ACCESSORY and the brake pedal
must be applied.
{Caution
Using a tool to force the key to
turn in the ignition could cause
damage to the switch or break the
key. Use the correct key, make
sure it is all the way in, and turn it
only with your hand. If the key
cannot be turned by hand, see
your dealer.
((STOPPING THE ENGINE/
LOCK/OFF): When the vehicle is
stopped, turn the ignition switch to
LOCK/OFF to turn the engine off.
Retained Accessory Power (RAP)
will remain active. See Retained
Accessory Power (RAP) on
page 9-19. This position locks the ignition,
transmission, and the steering
wheel when the key Is removed
from the ignition. The key can be
removed in LOCK/OFF.
The steering can bind with the
wheels turned off center. If this
happens, move the steering wheel
from right to left while turning the
key to ACC/ACCESSORY. If this
does not work, then the vehicle
needs service.
Do not turn the engine off when the
vehicle is moving. This will cause a
loss of power assist in the brake
and steering systems and disable
the airbags.
If the vehicle must be shut off in an
emergency:
1. Brake using a firm and steady
pressure. Do not pump the
brakes repeatedly. This may
deplete power assist, requiring
increased brake pedal force. 2. Shift the vehicle to N (Neutral).
This can be done while the
vehicle is moving. After shifting
to N (Neutral), firmly apply the
brakes and steer the vehicle to a
safe location.
3. Come to a complete stop, shift to P (Park), and turn the ignition
to LOCK/OFF. On vehicles with
an automatic transmission, the
shift lever must be in P (Park) to
turn the ignition switch to the
LOCK/OFF position.
4. Set the parking brake. See Parking Brake on page 9-27.{Warning
Turning off the vehicle while
moving may cause loss of power
assist in the brake and steering
systems and disable the airbags.
While driving, only shut the
vehicle off in an emergency.

Black plate (16,1)GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7576030) - 2015 - CRC - 8/18/14
9-16 Driving and Operating
If the vehicle cannot be pulled over,
and must be shut off while driving,
turn the ignition to ACC/
ACCESSORY.
ACC (ACC/ACCESSORY):This is
the position in which you can
operate the electrical accessories or
items plugged into the accessory
power outlets. This position unlocks
the ignition and steering wheel. Use
this position if the vehicle must be
pushed or towed.
R(ON/RUN): This position can be
used to operate the electrical
accessories and to display some
instrument panel warning and
indicator lights. This position can
also be used for service and
diagnostics, and to verify the proper
operation of the malfunction
indicator lamp as may be required
for emission inspection purposes.
The switch stays in this position
when the engine is running. The
transmission is also unlocked in this
position. If you leave the key in the
ACC/ACCESSORY or ON/RUN
position with the engine off, the battery could be drained. You may
not be able to start the vehicle if the
battery is allowed to drain for an
extended period of time.
/(START):
This is the position
that starts the engine. When the
engine starts, release the key. The
ignition switch will return to ON/RUN
for driving.
Key Lock Release
The vehicle has an electronic key
lock release system. This system is
to prevent ignition key removal
unless the shift lever is in P (Park).
The key lock release will not work if
the battery is charged less than
9-volts, or uncharged. Try charging
or jump starting the battery. See
Jump Starting on page 10-69
Starting the Engine
Move the shift lever to P (Park) or
N (Neutral). The engine will not start
in any other position. To restart the
engine when the vehicle is already
moving, use N (Neutral) only.
{Caution
Do not try to shift to P (Park) if the
vehicle is moving. If you do, you
could damage the transmission.
Shift to P (Park) only when the
vehicle is stopped.
{Caution
If you add electrical parts or
accessories, you could change
the way the engine operates. Any
resulting damage would not be
covered by the vehicle warranty.
See Add-On Electrical Equipment
on page 9-53.

Black plate (18,1)GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7576030) - 2015 - CRC - 8/18/14
9-18 Driving and Operating
To Use the Engine Coolant
Heater
1. Turn off the engine.
2. Open the hood and unwrap theelectrical cord. The bundled cord
is located on the driver side of
the engine compartment,
between the engine air cleaner
and the windshield washer fluid
reservoir. See Engine
Compartment Overview on
page 10-5.
Check the heater cord for
damage. If it is damaged, do not
use it. See your dealer for a
replacement. Inspect the cord for
damage yearly.
3. Plug the cord into a normal, grounded 110-volt AC outlet.
{Warning
Improper use of the heater cord
or an extension cord can damage
the cord and may result in
overheating and fire.
.Plug the cord into a
three-prong electrical utility
receptacle that is protected
by a ground fault detection
function. An ungrounded
outlet could cause an electric
shock.
.Use a weatherproof,
heavy-duty, 15 amp-rated
extension cord if needed.
Failure to use the
recommended extension cord
in good operating condition,
or using a damaged heater or
extension cord, could make it
(Continued)
Warning (Continued)
overheat and cause a fire,
property damage, electric
shock, and injury.
.Do not operate the vehicle
with the heater cord
permanently attached to the
vehicle. Possible heater cord
and thermostat damage could
occur.
.While in use, do not let the
heater cord touch vehicle
parts or sharp edges. Never
close the hood on the
heater cord.
.Before starting the vehicle,
unplug the cord, reattach the
cover to the plug, and
securely fasten the cord.
Keep the cord away from any
moving parts.
4. Before starting the engine, be sure to unplug and store the
cord as it was before to keep it

Black plate (19,1)GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7576030) - 2015 - CRC - 8/18/14
Driving and Operating 9-19
away from moving engine parts.
If you do not, it could be
damaged.
The length of time the heater should
remain plugged in depends on
several factors. Ask a dealer in the
area where you will be parking the
vehicle for the best advice on this.
Retained Accessory
Power (RAP)
These vehicle accessories can be
used for up to 10 minutes after the
ignition key is turned off:
.Audio System
.Power Windows
.Sunroof (if equipped)
Power to the windows and sunroof
will work up to 10 minutes or until a
door is opened.
The radio continues to work for
10 minutes or until the driver door is
opened. For an additional 10 minutes of
operation, close all the doors and
turn the key to ON/RUN and then
back to LOCK/OFF.
All these features will work when the
key is in the ON/RUN or ACC/
ACCESSORY positions.
Shifting Into Park
1. Hold the brake pedal down and
set the parking brake. See
Parking Brake on page 9-27 for
more information.
2. Move the shift lever into P (Park) by holding in the button on the
shift lever and pushing the shift
lever all the way toward the front
of the vehicle.
3. Turn the ignition key to LOCK/OFF.
4. Remove the key and take it with you. If you can leave the vehicle
with the ignition key in your
hand, the vehicle is in P (Park).
Leaving the Vehicle with the
Engine Running
{Warning
It can be dangerous to leave the
vehicle with the engine running.
It could overheat and catch fire.
It 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 on
page 9-19. If you are towing a
trailer, see Driving Characteristics
and Towing Tips on page 9-46.

Black plate (21,1)GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7576030) - 2015 - CRC - 8/18/14
Driving and Operating 9-21
Parking over Things
That Burn
{Warning
Things that can burn could touch
hot exhaust parts under the
vehicle and ignite. Do not park
over papers, leaves, dry grass,
or other things that can burn.
Engine Exhaust
{Warning
Engine 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.

Black plate (22,1)GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7576030) - 2015 - CRC - 8/18/14
9-22 Driving and Operating
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.
SeeShifting Into Park on page 9-19
and Engine Exhaust on page 9-21.
If parking on a hill and pulling a
trailer, see Driving Characteristics
and Towing Tips on page 9-46.
Automatic
Transmission
P (Park): This position locks the
front wheels. It is the best position
to use when starting the engine
because the vehicle cannot move
easily.
{Warning
It 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 on
page 9-19 andDriving
Characteristics and Towing Tips
on page 9-46.
Make sure the shift lever is fully in
P (Park) before starting the engine.
The vehicle has an automatic
transmission shift lock control
system. With the ignition in ON/
RUN, fully apply the regular brake,

Black plate (23,1)GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7576030) - 2015 - CRC - 8/18/14
Driving and Operating 9-23
then press the button on the back of
the shift lever before shifting from
P (Park). If you cannot shift out of
P (Park), ease pressure on the shift
lever, then push the shift lever all
the way into P (Park) as you
maintain brake application. Then
press the shift lever button and
move the shift lever into another
gear. SeeShifting out of Park on
page 9-20.
R (Reverse): Use this gear to
back up.
{Caution
Shifting 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 on page 9-9.
N (Neutral): In this position, the
engine does not connect with the
wheels. To restart the engine when
the vehicle is already moving, use
N (Neutral) only. Also, use
N (Neutral) when the vehicle is
being towed.
{Warning
Shifting into a drive gear while the
engine is running at high speed is
dangerous. Unless your foot is
firmly on the brake pedal, the
vehicle could move very rapidly.
You could lose control and hit
people or objects. Do not shift
into a drive gear while the engine
is running at high speed.
{Caution
Shifting out of P (Park) or
N (Neutral) with the engine
running at high speed may
damage the transmission. The
repairs would not be covered by
the vehicle warranty. Be sure the
engine is not running at high
speed when shifting the vehicle.
D (Drive): This position is for
normal driving. It provides the best
fuel economy. If you need more
power for passing, and you are:
.Going less than 56 km/h
(35 mph), push the accelerator
pedal about halfway down.
.Going about 56 km/h (35 mph) or
more, push the accelerator all
the way down.

Black plate (26,1)GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7576030) - 2015 - CRC - 8/18/14
9-26 Driving and Operating
Drive Systems
All-Wheel Drive
Vehicles with this feature transfer
engine power, as required, to all
four wheels. It is fully automatic, and
adjusts itself as needed for road
conditions.
When using a compact spare tire on
an AWD vehicle, the system
automatically detects the compact
spare and reduces AWD
performance to protect the system.
To restore full AWD operation and
prevent excessive wear on the
system, replace the compact spare
with a full-size tire as soon as
possible. SeeCompact Spare Tire
on page 10-68.
Brakes
Antilock Brake
System (ABS)
This vehicle has 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
might be heard while this test is
going on, and it might 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
on page 5-19. 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