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 (20,1)GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7576030) - 2015 - CRC - 8/18/14
9-20 Driving and Operating
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 10-69 for more information.
To shift out of P (Park):
1. Place the ignition in ON/RUN.
2. Apply the brake pedal.
3. Press the shift lever button.
4. 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.