
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Infotainment System 205
Voice Recognition If equipped, voice recognition allows
for hands-free operation within the
audio and phone applications. This
feature can be started by pressing
either the
g button on the steering
wheel or by selecting the
g on the
screen display.
However, not all features within
these areas are supported by voice
commands. Generally, only complex
tasks that require multiple manual
interactions to complete are
supported by voice commands.
For example, tasks that take more
than one or two button presses such
as selecting a song or artist to play
from a media device would be
supported by voice commands.
Other tasks, like adjusting the
volume or seeking up or down are
audio features that are easily
performed by pressing one or two
buttons, and are not supported by
voice commands. In general there are flexible ways to
speak commands for completing the
tasks. Most of them, except
destination entry and voice keypad,
can be completed in a single
command. If the task takes more
than one command to complete, the
first command would be to indicate
the kind of task that is to be
performed. The system replies with
prompts that lead through a dialog
to enter the necessary information.
Voice recognition can be used when
the ignition is on or when Retained
Accessory Power (RAP) is active.
See Retained Accessory Power
(RAP) 0 260 .
Using Voice Recognition Voice recognition becomes available
once the system has been
initialized. This begins when the
ignition is turned on. Initialization
may take a few moments. 1. Press
g on the steering wheel
control to activate voice
recognition, or select
g on the
infotainment screen on the
center stack.
.
If voice recognition is
started from the steering
wheel control, the
instrument cluster displays
the selections and visual
dialog content.
.
If voice recognition is
started from the
infotainment screen, the
selections and visual dialog
content are displayed on
both the center stack
display and the instrument
cluster display.
2. The audio system mutes and
the system plays a prompt
followed by a beep.
3. Wait until after the beep
completes, then clearly speak
one of the commands
described in this section. 

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Infotainment System 207For example, if the prompt
seems to be taking too long to
finish, or if what is being
prompted causes a need for an
immediate reply, press
g again
and wait for the beep.
.
Speak the command naturally,
not too fast, not too slow. Use
direct commands without a lot of
extra words.
.
Usually Phone and Audio
commands can be spoken in a
single command.
For example, “ Call Dave Smith
at work, ” “ Play ” followed by the
artist or song name, or “ Tune ”
followed by the radio station
number.
There is no need to memorize
specific command words. Direct
commands might be more clearly
understood by the system. An
example of a direct command would
be “ Call 555-1212. ” Examples of
these direct commands are
displayed on most of the screens
while a voice session is active.
If “ Phone ” or “ Phone Commands, ” is stated, the system understands that
a phone call is requested and will
respond with questions until enough
details are gathered.
If the phone number has been
saved with a name and a place, the
direct command should include
both, for example “ Call Dave Smith
at work. ”
Using Voice Recognition for
List Options When a list is displayed, a voice
prompt will ask to confirm or select
an option from that list. A selection
can be made by manually selecting
the item, or by speaking the line
number for the item to select.
When a screen contains a list,
options may be available but not
displayed. The list on a voice
recognition screen functions the
same as a list on other screens.
Scrolling can be used to help
display other entries from the list.
Manually scrolling or paging the list
on a screen during a voice
recognition session suspends the
current voice recognition event and plays the prompt “ Make your
selection from the list using the
manual controls or press the Back
button to try again. ”
If manual selection takes more than
15 seconds, the session terminates
and prompts that it has timed out.
The screen returns back to the
screen where voice recognition was
initiated.
The Back Command
Say “ Back ” or press the Back button
to go to the previous screen.
If in voice recognition, and “ Back ” is
stated all the way through to the
initial screen, then “ Back ” is stated
one more time, the voice recognition
session will cancel.
Help
Say “ Help ” on any voice recognition
screen and the help prompt for the
screen is played. Additionally, a
pop-up displays a text version of the
help prompt. Depending on how
voice recognition was initiated, the
Help pop-up will either display on
the instrument cluster or the 

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 257This position locks the ignition and
steering wheel. It also locks the
transmission. 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 may 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). Turn the ignition to
LOCK/OFF.
4. Set the parking brake. See
Parking Brake 0 281 .
The shift lever must be in P (Park)
to turn the ignition switch to
LOCK/OFF.
{ WarningTurning 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.
If the vehicle cannot be pulled over,
and must be shut off while driving,
turn the ignition to ACC/
ACCESSORY. CautionUsing 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.
1 (ACC/ACCESSORY) : This
position lets things like the radio
and the windshield wipers operate
while the engine is off. It also
unlocks the steering wheel. Use this
position if the vehicle must be
pushed or towed.
2 (ON/RUN) : This position can be
used to operate the electrical
accessories and to display some
instrument cluster 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. 

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 265Warning (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 0 262 and
Engine Exhaust 0 264 .
If parking on a hill and pulling a
trailer, see Driving Characteristics
and Towing Tips 0 303 .Automatic
Transmission If equipped, there is an electronic
shift lever position indicator within
the instrument cluster. This display
comes on when the ignition key is
turned on.
There are several different positions
for the shift lever.
Heavy-Duty 6-Speed Automatic
Transmission Shown, Others
Similar
See “ Range Selection Mode ” under
Manual Mode 0 268 .
P : This position locks the rear
wheels. Use P (Park) when starting
the engine because the vehicle
cannot move easily. 

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 271Low Traction Mode If equipped, Low Traction Mode
assists in vehicle acceleration when
road conditions are slippery, such
as with ice or snow. While the
vehicle is at a stop, select L2 using
Range Selection Mode. This will
limit torque to the wheels and help
to prevent the tires from spinning.
Tow/Haul Mode
Vehicles with an automatic
transmission have a Tow/Haul
Mode. The Tow/Haul Mode adjusts
the transmission shift pattern to
reduce shift cycling. This provides increased performance, vehicle
control, and enhanced transmission
and engine cooling when driving
down steep hills or mountain
grades, when towing, or when
hauling heavy loads.
The selector button is on the end of
the shift lever. Turn the Tow/Haul
Mode on and off by pressing the
button. When the Tow/Haul Mode is
enabled, a light on the instrument
cluster will come on.
For an eAssist vehicle, the Stop/
Start function will become
unavailable when Tow/Haul Mode is
active.
For an eAssist vehicle, the
Regenerative Braking functionality is
disabled when using the Tow/Haul
Mode. See the eAssist supplement.
See Tow/Haul Mode Light 0 153 and
Hill and Mountain Roads 0 245 .
Also see “ Tow/Haul Mode ” under
Towing Equipment 0 325 . Tow/Haul Mode Grade Braking Tow/Haul Mode Grade Braking is
only enabled while the Tow/Haul
Mode is selected and the vehicle is
not in the Range Selection Mode.
See “ Tow/Haul Mode ” listed
previously and Manual Mode 0 268 .
Tow/Haul Mode Grade Braking
assists in maintaining desired
vehicle speeds when driving on
downhill grades by using the engine
and transmission to slow the
vehicle.
If equipped, on vehicles with a
gasoline engine, to disable or
enable Tow/Haul Grade Braking
within the current ignition key cycle,
press and hold the Tow/Haul button
for five seconds. When the button is
released, the requested mode
change is made. A DIC message is
displayed. 

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 283intended path. Trailer Sway Control
(TSC) is also on automatically when
the vehicle is started. See Trailer
Sway Control (TSC) 0 334 .
If cruise control is being used and
traction control or StabiliTrak begins
to limit wheel spin, cruise control will
disengage. Cruise control may be
turned back on when road
conditions allow.
Both systems come on
automatically when the vehicle is
started and begins to move. The
systems may be heard or felt while
they are operating or while
performing diagnostic checks. This
is normal and does not mean there
is a problem with the vehicle.
It is recommended to leave both
systems on for normal driving
conditions, but it may be necessary
to turn TCS off if the vehicle gets
stuck in sand, mud, ice, or snow.
See If the Vehicle Is Stuck 0 247
and “ Turning the Systems Off and
On ” later in this section. When the transfer case (if equipped)
is in Four-Wheel Drive Low, the
stability system is automatically
disabled,
g comes on, and the
appropriate message will appear on
the DIC. Both traction control and
StabiliTrak are automatically
disabled in this condition.
The indicator light for both systems
is in the instrument cluster. This
light will:
.
Flash when TCS is limiting
wheel spin
.
Flash when StabiliTrak is
activated
.
Turn on and stay on when either
system is not working
If either system fails to turn on or to
activate, a message displays in the
Driver Information Center (DIC), and
d comes on and stays on to indicate that the system is inactive
and is not assisting the driver in
maintaining control. The vehicle is
safe to drive, but driving should be
adjusted accordingly.
If
d comes on and stays on:
1. Stop the vehicle.
2. Turn the engine off and wait
15 seconds.
3. Start the engine.
Drive the vehicle. If
d comes on
and stays on, the vehicle may need
more time to diagnose the problem.
If the condition persists, see your
dealer.
Turning the Systems Off
and On
The button for TCS and StabiliTrak
is on the center stack. 

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
284 Driving and Operating CautionDo not repeatedly brake or
accelerate heavily when TCS is
off. The vehicle driveline could be
damaged.
To turn off only TCS, press and
release
g . The traction off light
idisplays in the instrument cluster.
The appropriate message will
display in the DIC. To turn TCS on
again, press and release
g . The
traction off light
i displayed in the
instrument cluster will turn off.
If TCS is limiting wheel spin when
gis pressed, the system will not turn
off until the wheels stop spinning.
To turn off both TCS and StabiliTrak,
press and hold
g until the traction
off light
i and the StabiliTrak OFF
light
g come on and stay on in the
instrument cluster, then release. The
appropriate message will display in
the DIC. To turn TCS and StabiliTrak on
again, press and release
g . The
traction off light
i and the
StabiliTrak OFF light
g in the
instrument cluster turn off.
StabiliTrak will automatically turn on
if the vehicle exceeds 56 km/h
(35 mph). Traction control will
remain off.
The vehicle has a Trailer Sway
Control (TSC) feature and a Hill
Start Assist (HSA) feature.
See Trailer Sway Control (TSC)
0 334 or Hill Start Assist (HSA)
0 282 .
Adding accessories can affect the
vehicle performance. See
Accessories and Modifications
0 343 .
Hill Descent
Control (HDC) If equipped, Hill Descent Control
(HDC) sets and maintains vehicle
speed while driving down steep grades in a forward or reverse gear.
The HDC switch is on the center
stack, below the climate controls.
Press
5 to enable or disable HDC.
Vehicle speed must be below
50 km/h (31 mph).
When enabled, the HDC light
displays on the instrument cluster.
A blinking HDC light indicates the
system is actively applying the
brakes to maintain vehicle speed.
HDC can maintain vehicle speeds
between 1 and 30 km/h (1 and
19 mph) on grades greater than or
equal to 10%.
If HDC is to be used for more than
three minutes or on grades steeper
than 25%, the transfer case should
be put into Four-Wheel Drive Low
(4
n ) to reduce the possibility of
brake overheating. 

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
286 Driving and Operating If equipped with an Allison or
Hydra-Matic 6-speed automatic
transmission, see “ Tow/Haul Mode
Grade Braking ” under Tow/Haul
Mode 0 271 for an explanation of
how cruise control interacts with the
Range Selection Mode, Tow/Haul
Mode, and Grade Braking systems.
If the cruise control is being used
and the Traction Control System
(TCS) or StabiliTrak begins to limit
wheel spin, the cruise control will
automatically disengage. See
Traction Control/Electronic Stability
Control 0 282 . If a collision alert
occurs when cruise control is
activated, cruise control is
disengaged. See Forward Collision
Alert (FCA) System 0 292 . When
road conditions allow you to safely
use it again, cruise control can be
turned back on.
If the brakes are applied, the cruise
control disengages. 5 : Press to turn the system on or
off. A white indicator comes on in
the instrument cluster when cruise
control is on and turns off when
cruise control is off.
+RES : If there is a set speed in
memory, press briefly to resume to
that speed or press and hold to
accelerate. If cruise control is
already active, use to increase
vehicle speed.
SET − : Press briefly to set the
speed and activate cruise control.
If cruise control is already active,
use to decrease vehicle speed. * : Press to disengage cruise
control without erasing the set
speed from memory.
Setting Cruise Control
If
5 is on when not in use, SET − or
+RES could get pressed and go into
cruise when not desired. Keep
5 off when cruise is not being used.
1. Press
5 to turn the cruise
system on.
2. Get up to the desired speed.
3. Press and release SET − .
4. Remove your foot from the
accelerator.
The cruise control indicator on the
instrument cluster turns green after
cruise control has been set to the
desired speed. See Instrument
Cluster 0 138 .