Black plate (52,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-52 Driving and Operating
HDC will remain enabled between
22 and 60 km/h (14 and 37 mph);
however vehicle speed cannot be
set or maintained in this range.
It 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.
5must be pressed
again to re-enable HDC.
When enabled, if the vehicle is at a
speed above 22 km/h (14 mph) and
less than 60 km/h (37 mph), a DIC
message will display. See Vehicle
Speed Messages on page 5-42.
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.
Cruise Control
With cruise control a speed of about
40 km/h (25 mph) or more can be
maintained without keeping your
foot on the accelerator. Cruise
control does not work at speeds
below about 40 km/h (25 mph).
{Warning
Cruise control can be dangerous
where you cannot drive safely at
a steady speed. Do not use
cruise control on winding roads or
in heavy traffic.
Cruise control can be dangerous
on slippery roads. On such roads,
fast changes in tire traction can
cause excessive wheel slip, and
you could lose control. Do not use
cruise control on slippery roads. If equipped with an Allison or
Hydra-Matic 6-speed automatic
transmission, see
“Tow/Haul Mode
Grade Braking” underTow/Haul
Mode on page 9-39 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 on page 9-49. If a collision
alert occurs when cruise control is
activated, cruise control is
disengaged. See Forward Collision
Alert (FCA) System on page 9-59.
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.
Black plate (54,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-54 Driving and Operating
The speedometer reading can be
displayed in either English or metric
units. SeeInstrument Cluster on
page 5-9. The increment value used
depends on the units displayed.
Reducing Speed While Using
Cruise Control
If the cruise control system is
already activated:
.Press and hold the SET– button
until the desired lower speed is
reached, then release it.
.To slow down in small
increments, briefly press the
SET– button. For each press,
the vehicle goes about 1.6 km/h
(1 mph) slower.
The speedometer reading can be
displayed in either English or metric
units. See Instrument Cluster on
page 5-9. The increment value used
depends on the units displayed. Passing Another Vehicle While
Using Cruise Control
Use the accelerator pedal to
increase the vehicle speed. When
you take your foot off the pedal, the
vehicle will slow down to the
previous set cruise speed. While
pressing the accelerator pedal or
shortly following the release to
override cruise control, briefly
pressing the SET–
button will result
in cruise control set to the current
vehicle speed.
Using Cruise Control on Hills
How well the cruise control works
on hills depends on the vehicle
speed, the load, and the steepness
of the hills. When going up steep
hills, pressing the accelerator pedal
may be necessary to maintain
vehicle speed. While going downhill:
.Vehicles with a 6-speed
automatic transmission and a
gasoline engine have Cruise
Grade Braking to help maintain
driver selected speed.
Cruise Grade Braking is enabled
when the vehicle is started and
cruise control is active. It is not
enabled in Range Selection
Mode. It assists in maintaining
driver selected speed when
driving on downhill grades by
using the engine and
transmission to slow the vehicle.
To disable and enable Cruise
Grade Braking for the current
ignition key cycle, press and
hold the Tow/Haul button for
five seconds. A DIC message
displays. See
Transmission
Messages on page 5-39.
.Vehicles with a diesel engine
have Cruise Grade Braking
enabled when Tow/Haul Mode is
on, the exhaust brake is on,
or both are on.
Black plate (56,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-56 Driving and Operating
Audible or Safety Alert Seat
Some driver assistance features
alert the driver of obstacles by
beeping. To change the volume of
the warning chime, see“Comfort
and Convenience” underVehicle
Personalization on page 5-42.
If equipped with the Safety Alert
Seat, the driver seat cushion may
provide a vibrating pulse alert
instead of beeping. To change this,
see “Collision/Detection Systems”
under Vehicle Personalization on
page 5-42.
Assistance Systems for
Parking or Backing
If equipped, the Rear Vision Camera
(RVC), Rear Parking Assist (RPA),
and Front Park Assist (FPA) may
help the driver park or avoid objects.
Always check around the vehicle
when parking or backing. The RVC and RPA will not work
properly if the tailgate is down. If the
tailgate is down, do not use these
systems.
Rear Vision Camera (RVC)
When the vehicle is shifted into
R (Reverse), the RVC displays an
image of the area behind the vehicle
in the center stack display. The
previous screen displays when the
vehicle is shifted out of R (Reverse)
after a short delay. To return to the
previous screen sooner, press a
button on the infotainment system,
shift into P (Park), or reach a vehicle
speed of 8 km/h (5 mph).
1. View Displayed by the
Camera
1. View Displayed by theCamera
2. Corners of the Rear Bumper
Black plate (57,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-57
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 on
the RVC screen to show where the
RPA has detected an object. This
triangle changes from amber to red
and increases in size the closer the
object.
{Warning
The RVC system does not display
children, pedestrians, bicyclists,
crossing traffic, animals, or any
other object located outside the
camera's field of view, below the
bumper, or under the vehicle.
Perceived distances may be
different from actual distances.
Do not back the vehicle using
only the RVC screen. Failure to
use proper care before backing(Continued)
Warning (Continued)
may result in injury, death,
or vehicle damage. Always check
behind and around the vehicle
before backing.
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,
or vehicle damage, even with
parking assist, always check the
area around the vehicle and
check all mirrors before moving
forward or backing.
Black plate (58,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-58 Driving and Operating
The instrument cluster may have a
parking assist display with bars that
show“distance to object” and object
location information for RPA, and on
some vehicles, for FPA. As the
object gets closer, more bars light
up and the bars change color from
yellow to amber to red.
When an object is first detected in
the rear, one beep will be heard
from the rear, or both sides of the
Safety Alert Seat will pulse two
times. When an object is very close
(<0.6 m (2 ft) in the vehicle rear,
or <0.3 m (1 ft) in the vehicle front),
a continuous beep will sound from the front or rear, or both sides of the
Safety Alert Seat will pulse five
times. Beeps for FPA are higher
pitched than for RPA.
Turning the Features On or Off
TheXbutton on the center stack
is used to turn on or off the Front
and Rear Parking Assist. The
indicator light in the button comes
on when the features are on and
turns off when the features have
been disabled.
Front and Rear Parking Assist can
be turned off, on, or on with towbar
through vehicle personalization. See
“Park Assist” underVehicle
Personalization on page 5-42. If the
parking assist is turned off through
vehicle personalization, the parking
assist button on the center stack will be disabled. To turn the parking
assist on again, select On in the
vehicle personalization menu. The
On with Towbar setting allows for
the parking assist to work properly
with a small item attached to the
trailer hitch. Turn off parking assist
when towing a trailer.
To turn the rear parking assist
symbols or guidance lines, see
“Rear Camera”
underVehicle
Personalization on page 5-42.Disconnecting the Rear Vision
Camera (RVC)
The RVC must be disconnected if
the tailgate needs to be removed.
The RVC is disconnected by
removing the connector from the
electrical junction block mounted on
the left side of the cross member of
the vehicle frame. After
disconnecting, the cap mounted
next to the camera connector must
be relocated so that the open
terminals on the junction block are
covered.
Black plate (59,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-59
Assistance Systems for
Driving
If equipped, when driving the
vehicle, Forward Collision Alert
(FCA) and Lane Departure Warning
(LDW) can help to avoid a crash or
reduce crash damage.
Forward Collision Alert
(FCA) System
If equipped, the FCA system may
help to avoid or reduce the harm
caused by front-end crashes. When
approaching a vehicle ahead too
quickly, FCA provides a red flashing
alert on the windshield and rapidly
beeps or pulses the driver seat.
FCA also lights an amber visual
alert if following another vehicle
much too closely.
FCA detects vehicles within a
distance of approximately 60 m
(197 ft) and operates at speeds
above 40 km/h (25 mph).
{Warning
FCA is a warning system and
does not apply the brakes. When
approaching a slower-moving or
stopped vehicle ahead too rapidly,
or when following a vehicle too
closely, FCA may not provide a
warning with enough time to help
avoid a crash. FCA does not warn
of pedestrians, animals, signs,
guardrails, bridges, construction
barrels, or other objects. Be ready
to take action and apply the
brakes. For more information, see
Defensive Driving on page 9-3.
FCA can be disabled with the FCA
steering wheel control.
Detecting the Vehicle Ahead
FCA warnings will not occur unless
the FCA system detects a vehicle
ahead. When a vehicle is detected
ahead, the vehicle-ahead indicator
will display green. Vehicles may not
be detected on curves, highway exit
ramps, or hills; or due to poor
visibility. FCA will not detect another
vehicle ahead until it is completely
in the driving lane.
{Warning
FCA does not provide a warning
to help avoid a crash, unless it
detects a vehicle. FCA may not
detect a vehicle ahead if the FCA
sensor is blocked by dirt, snow, (Continued)
Black plate (60,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-60 Driving and Operating
Warning (Continued)
or ice, or if the windshield is
damaged. It may also not detect a
vehicle on winding or hilly roads,
or in conditions that can limit
visibility such as fog, rain,
or snow, or if the headlamps or
windshield are not cleaned or in
proper condition. Keep the
windshield, headlamps, and FCA
sensors clean and in good repair.Collision Alert
When your vehicle approaches
another detected vehicle too rapidly,
the red FCA display will flash on the
windshield. Also, eight rapid
high-pitched beeps will sound from
the front, or both sides of the Safety
Alert Seat will pulse five times.
When this Collision Alert occurs, the
brake system may prepare for driver
braking to occur more rapidly which
can cause a brief, mild deceleration.
Continue to apply the brake pedal as needed. Cruise control may be
disengaged when the Collision Alert
occurs.
Tailgating Alert
The vehicle ahead indicator will
display amber when you are
following a vehicle ahead much too
closely.
Black plate (67,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-67
Be careful not to spill fuel. Do not
top off or overfill the tank and wait a
few seconds after you have finished
pumping before removing the
nozzle. Clean fuel from painted
surfaces as soon as possible. See
Exterior Care on page 10-96.
When replacing the fuel cap, turn it
clockwise until it clicks. It will require
more effort to turn the fuel cap on
the last turn as you tighten it. Make
sure the cap is fully installed. The
diagnostic system can determine if
the fuel cap has been left off or
improperly installed. This would
allow fuel to evaporate into the
atmosphere. SeeMalfunction
Indicator Lamp on page 5-18.
The TIGHTEN GAS CAP message
displays on the Driver Information
Center (DIC) if the fuel cap is not
properly installed. See Fuel System
Messages on page 5-35 for more
information.{Warning
If a fire starts while you are
refueling, do not remove the
nozzle. Shut off the flow of fuel by
shutting off the pump or by
notifying the station attendant.
Leave the area immediately.
{Caution
If a new fuel cap is needed, be
sure to get the right type of cap
from your dealer. The wrong type
of fuel cap may not fit properly,
may cause the malfunction
indicator lamp to light, and could
damage the fuel tank and
emissions system. See
Malfunction Indicator Lamp on
page 5-18.
Filling a Portable Fuel
Container
{Warning
Filling a portable fuel container
while it is in the vehicle can cause
fuel vapors that can ignite either
by static electricity or other
means. You or others could be
badly burned and the vehicle
could be damaged. Always:
.Use approved fuel
containers.
.Remove the container from
the vehicle, trunk, or pickup
bed before filling.
.Place the container on the
ground.
.Place the nozzle inside the fill
opening of the container
before dispensing fuel, and
(Continued)