Black plate (15,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Driving and Operating 9-15
{WARNING
Things you put inside the
vehicle can strike and injure
people in a sudden stop or
turn, or in a crash.
.Put things in the cargo
area of the vehicle. Try to
spread the weight evenly.
.Never stack heavier
things, like suitcases,
inside the vehicle so that
some of them are above
the tops of the seats.
.Do not leave an
unsecured child restraint
in the vehicle.
.When you carry something
inside the vehicle, secure
it whenever you can.
.Do not leave a seat folded
down unless you need to.
Starting and
Operating
New Vehicle Break-In
Notice: The vehicle does not
need an elaborate break-in.
But it will perform better in the
long run if you follow these
guidelines:
.If you have all-wheel drive,
keep your speed at 88 km/h
(55 mph) or less for the first
805 km (500 mi).
.Do not drive at any one
constant speed, fast or slow,
for the first 805 km (500 mi).
Do not make full-throttle
starts. Avoid downshifting to
brake or slow the vehicle.
.Avoid making hard stops for
the first 322 km (200 mi) 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. See Driving
Characteristics and Towing
Tips on page 9‑45 for the
trailer towing capabilities of
your vehicle and more
information.
Following break‐in, engine speed
and load can be gradually
increased.
Black plate (16,1)GMC Acadia/Acadia Denali Owner Manual - 2012
9-16 Driving and Operating
Ignition Positions
The ignition switch has four different
positions.
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.
Notice: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 9‑20.
This position locks the ignition
and transmission. The key can be
removed in LOCK/OFF.
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 9‑28.
{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 (17,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Driving and Operating 9-17
If the vehicle cannot be pulled
over, and must be shut off while
driving, turn the ignition to
ACC/ACCESSORY.
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.
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
Vehicles with an automatic
transmission are equipped with 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 10‑78.
Black plate (18,1)GMC Acadia/Acadia Denali Owner Manual - 2012
9-18 Driving and Operating
If charging or jump starting the
battery does not work, there is a
manual key lock release. Locate the
hole below the ignition lock. Insert a
tool or key into the opening. Locate
the lever, and press it toward the
driver while removing the key from
the ignition.
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.
Notice: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.
Starting Procedure
1. With your foot off the accelerator
pedal, turn the ignition to START.
When the engine starts, let go of
the key. The idle speed will slow
down as the engine warms. Do not race the engine
immediately after starting it.
Operate the engine and
transmission gently to allow
the oil to warm up and lubricate
all moving parts.
The vehicle has a
Computer-Controlled Cranking
System. This feature assists in
starting the engine and protects
components. If the ignition key is
turned to the START position,
and then released when the
engine begins cranking, the
engine will continue cranking
for a few seconds or until the
vehicle starts. If the engine
does not start and the key is
held in START, cranking will be
stopped after 15 seconds to
prevent cranking motor damage.
To prevent gear damage, this
system also prevents cranking if
the engine is already running.
Engine cranking can be stopped
by turning the ignition switch to
the ACC/ACCESSORY or
LOCK/OFF position.Notice:
Cranking the engine for
long periods of time, by returning
the key to the START position
immediately after cranking has
ended, can overheat and damage
the cranking motor, and drain the
battery. Wait at least 15 seconds
between each try, to let the
cranking motor cool down.
2. If the engine does not start
after five to 10 seconds,
especially in very cold weather
(below 0°F or −18°C), it could be
flooded with too much gasoline.
Try pushing the accelerator
pedal all the way to the floor
and holding it there as you hold
the key in START for up to a
maximum of 15 seconds.
Wait at least 15 seconds
between each try, to allow the
cranking motor to cool down.
When the engine starts, let go
of the key and accelerator.
Black plate (19,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Driving and Operating 9-19
If the vehicle starts briefly but
then stops again, repeat these
steps. This clears the extra
gasoline from the engine.
Do not race the engine
immediately after starting it.
Operate the engine and
transmission gently until the oil
warms up and lubricates all
moving parts.
Notice: The engine is designed to
work with the electronics in the
vehicle. If you add electrical parts
or accessories, you could change
the way the engine operates.
Before adding electrical
equipment, check with your
dealer. If you do not, the engine
might not perform properly.
Any resulting damage would
not be covered by the vehicle
warranty.Engine Heater
The engine coolant heater can
provide easier starting and better
fuel economy during engine
warm-up in cold weather conditions
at or below 0°F (−18°C). Vehicles
with an engine coolant heater
should be plugged in at least four
hours before starting. Some models
may have an internal thermostat in
the cord 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 side of the
engine compartment. It is routed
around the windshield washer
fluid reservoir.
3. Plug the cord into a normal, grounded 110-volt AC outlet.
{WARNING
Plugging the cord into an
ungrounded outlet could cause an
electrical shock. Also, the wrong
kind of extension cord could
overheat and cause a fire. 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.
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.
Black plate (20,1)GMC Acadia/Acadia Denali Owner Manual - 2012
9-20 Driving and Operating
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
{WARNING
It can be 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. 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, use the steps
that follow. If you are pulling a
trailer, see Driving Characteristics
and Towing Tips on page 9‑45.
1. Hold the brake pedal down and set the parking brake.
See Parking Brake on page 9‑28
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.
The vehicle could move suddenly
if the shift lever is not fully in
P (Park) with the parking brake
firmly set. 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.
Black plate (21,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Driving and Operating 9-21
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 have moved
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
pushing the button.
If you can, it means that the shift
lever was not fully locked in
P (Park).
Torque Lock
Torque lock is when the weight
of the vehicle puts too much
force on the parking pawl in the
transmission. This happens when
parking on a hill and shifting the
transmission into P (Park) is not
done properly and then it is
difficult to shift out of P (Park).
To prevent torque lock, set the
parking brake and then shift into
P (Park). To find out how, see
“Shifting Into Park”listed previously. If torque lock does occur, your
vehicle may need to be pushed
uphill by another vehicle to relieve
the parking pawl pressure, so you
can shift out of P (Park).
Shifting out of Park
The 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
P (Park) with the shift lever
button fully released, and
.Prevent movement of the shift
lever out of P (Park), 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 the vehicle has an uncharged
battery or a battery with low voltage,
try charging or jump starting the
battery. See
Jump Starting on
page 10‑78 for more information.
To shift out of P (Park):
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
P (Park):
1. Fully release the shift lever button.
2. While holding down the brake pedal, press the shift lever
button again.
3. Move the shift lever to the desired position.
If you still cannot move the shift
lever from P (Park), see your dealer.
Black plate (22,1)GMC Acadia/Acadia Denali Owner Manual - 2012
9-22 Driving and Operating
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.(Continued)
WARNING (Continued)
.The vehicle exhaust system
has been modified, damaged
or improperly repaired.
.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.