light GMC SIERRA DENALI 2015 Owners Manual

Black plate (51,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-51press and release the
g button. The
traction off light
i displayed in the
instrument cluster will turn off.
If TCS is limiting wheel spin when
the
g button is pressed, the system
will not turn off until the wheels stop
spinning.
To turn off both TCS and StabiliTrak,
press and hold the
g button 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. See Ride Control System
Messages on page 5-36 .
To turn TCS and StabiliTrak on
again, press and release the
gbutton. 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) on
page 9-87 or Hill Start Assist (HSA)
on page 9-48 .
Adding accessories can affect the
vehicle performance. See
Accessories and Modifications on
page 10-3 .
Hill Descent
Control (HDC) If equipped, HDC can be used when
driving downhill. It sets and
maintains vehicle speed while
descending a very steep incline 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).
The HDC light displays on the
instrument cluster when enabled.
HDC can maintain vehicle speeds
between 3 and 22 km/h (2 and
14 mph) on an incline greater than
or equal to a 10% grade. A blinking
HDC light indicates the system is
actively applying the brakes to
maintain vehicle speed.
When HDC is activated, the initial
HDC speed is set to the current
driving speed. It can be increased or
decreased by applying the
accelerator or brake pedal. This
adjusted speed becomes the new
set speed.

Black plate (55,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-55For other forms of Grade Braking,
see Automatic Transmission on
page 9-33 , Tow/Haul Mode on
page 9-39 , and Hill Descent Control
(HDC) on page 9-51 .
Ending Cruise Control
There are four ways to end cruise
control: .
Step lightly on the brake pedal. .
Press
* ..
Shift the transmission to
N (Neutral). .
To turn off cruise control,
press
5 .
Erasing Speed Memory
The cruise control set speed is
erased from memory if
5 is pressed
or the ignition is turned off. Driver Assistance
Systems This vehicle may have features that
work together to help avoid crashes
or reduce crash damage while
driving, backing, and parking. Read
this entire section before using
these systems.
{ WarningDo not rely on the Driver
Assistance Systems. These
systems do not replace the need
for paying attention and driving
safely. You may not hear or feel
alerts or warnings provided by
these systems. Failure to use
proper care when driving may
result in injury, death, or vehicle
damage. See Defensive Driving
on page 9-3 .
(Continued) Warning (Continued) Under many conditions, these
systems will not: .
Detect children, pedestrians,
bicyclists, or animals. .
Detect vehicles or objects
outside the area monitored by
the system. .
Work at all driving speeds. .
Warn you or provide you with
enough time to avoid a crash. .
Work under poor visibility or
bad weather conditions. .
Work if the detection sensor
is not cleaned or is covered
by ice, snow, mud, or dirt.
Complete attention is always
required while driving, and you
should be ready to take action
and apply the brakes and/or steer
the vehicle to avoid crashes.

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
The
X button 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 ” under Vehicle
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 ” under Vehicle
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). { WarningFCA 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 (62,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-62 Driving and Operating Warning (Continued) proper condition; or if the sun
shines directly into the
camera. .
Detect road edges. .
Detect lanes on winding or
hilly roads.
If LDW only detects lane
markings on one side of the road,
it will only warn you when
departing the lane on the side
where it has detected a lane
marking. Always keep your
attention on the road and
maintain proper vehicle position
within the lane, or vehicle
damage, injury, or death could
occur. Always keep the
windshield, headlamps, and
camera sensors clean and in
good repair. Do not use LDW in
bad weather conditions. How the System Works The LDW camera sensor is on the
windshield ahead of the rearview
mirror.
To turn LDW on and off, press
@ on
the center stack. The control
indicator will light when LDW is on.
When LDW is on,
@ is green if
LDW is available to warn of a lane
departure. If the vehicle crosses a
detected lane marking without using
the turn signal in that direction,
@changes to amber and flashes.
Additionally, there will be three
beeps, or the driver seat will pulse
three times on the right or left,
depending on the lane departure
direction. When the System Does Not
Seem to Work Properly The system may not detect lanes as
well when there are: .
Close vehicles ahead. .
Sudden lighting changes, such
as when driving through tunnels. .
Banked roads.
If the LDW system is not functioning
properly when lane markings are
clearly visible, cleaning the
windshield may help.
LDW alerts may occur due to tar
marks, shadows, cracks in the road,
temporary or construction lane
markings, or other road
imperfections. This is normal system
operation; the vehicle does not need
service. Turn LDW off if these
conditions continue.

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 9-67Be 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. See Malfunction
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. { WarningIf 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.
{ CautionIf 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
{ WarningFilling 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)

Black plate (68,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-68 Driving and Operating Warning (Continued) keep it in contact with the fill
opening until filling is
complete. .
Fill the container no more
than 95% full to allow for
expansion. .
Do not smoke, light matches,
or use lighters while
pumping fuel. .
Avoid using cell phones or
other electronic devices. Trailer Towing General Towing
Information Only use towing equipment that has
been designed for the vehicle.
Contact your dealer or trailering
dealer for assistance with preparing
the vehicle for towing a trailer. Read
the entire section before towing a
trailer.
For towing a disabled vehicle, see
Towing the Vehicle on page 10-91 .
For towing the vehicle behind
another vehicle such as a motor
home, see Recreational Vehicle
Towing on page 10-91 .
Driving Characteristics
and Towing Tips Driving with a Trailer
When towing a trailer: .
Become familiar with the state
and local laws that apply to
trailer towing. .
Do not tow a trailer during the
first 800 km (500 mi) to prevent
damage to the engine, axle,
or other parts. .
Then during the first 800 km
(500 mi) of trailer towing, do not
drive over 80 km/h (50 mph) and
do not make starts at full throttle. .
Vehicles can tow in D (Drive).
Shift the transmission to a lower
gear if the transmission shifts
too often under heavy loads and/
or hilly conditions. .
Turn off Park Assist when
towing.
{ Warning
When towing a trailer, exhaust
gases may collect at the rear of
the vehicle and enter if the
liftgate, trunk/hatch, or rear-most
window is open.
(Continued)

Black plate (79,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-79Vehicle Series Trailer Weight Weight Distributing Hitch
Usage Hitch Distribution
1500 Up to 3175 kg (7,000 lb) Optional Refer to trailer
manufacturer ’ s
recommendation
1500 Over 3175 kg (7,000 lb) Required 50%
2500/3500 Up to 8165 kg (18,000 lb) Optional Refer to trailer
manufacturer ’ s
recommendation
1. Body to Ground Distance
2. Front of Vehicle When using a weight-distributing
hitch, measure distance (1) before
coupling the trailer to the hitch ball.
Measure the height again after the
trailer is coupled and adjust the
spring bars so the distance (1) is as
close as possible to halfway
between the two measurements.
Fifth-Wheel and Gooseneck
Trailering
Fifth-wheel and gooseneck trailers
can be used with many pickup
models. These trailers place a
larger percentage of the weight (kingpin weight) on the tow vehicle
than conventional trailers. Make
sure this weight does not cause the
vehicle to exceed GAWR or GVWR.
Fifth-wheel or gooseneck kingpin
weight should be 15 to 25% of the
trailer weight up to the maximum
amount specified in the trailering
chart for the vehicle. See “ Weight of
the Trailer ” under Trailer Towing on
page 9-71 .
The hitch should be located in the
pickup bed so that its centerline is
over or slightly in front of the rear
axle. Take care that it is not so far

Black plate (81,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-81Basic Trailer Wiring
All regular, double cab, and crew
cab pickups have a seven-wire
trailer towing harness.
For vehicles not equipped with
heavy-duty trailering, the harness is
secured to the vehicle's frame
behind the spare tire mount. The
harness requires the installation of a
trailer connector, which is available
through your dealer.
Heavy-Duty Trailer Wiring Harness
Package For vehicles equipped with
heavy-duty trailering, the harness
connector is mounted in the bumper.
The seven-wire harness contains
the following trailer circuits: .
Green/Violet: Left Stop/Turn
Signal .
Yellow/Gray: Right Stop/Turn
Signal .
Gray/Brown: Taillamps/Parking
Lamps .
White: Ground .
White/Green: Back-up Lamps .
Red/Green: Battery Feed .
Dark Blue: Trailer Brake
If charging a remote (non-vehicle)
battery, press the Tow/Haul Mode
button, if equipped, at the end of the
shift lever. This will boost the
vehicle system voltage and properly
charge the battery. If the trailer is
too light for Tow/Haul Mode, or the
vehicle is not equipped with Tow/ Haul, turn on the headlamps as a
second way to boost the vehicle
system and charge the battery.
Camper/Fifth-Wheel Trailer Wiring
Package
The seven-wire camper harness is
under the rear bumper, attached to
the frame near the rear
crossmember. A connector must be
added to the wiring harness that
connects to the camper.
The harness contains the following
camper/trailer circuits: .
Green/Violet: Left Stop/Turn
Signal .
Yellow/Gray: Right Stop/Turn
Signal .
Gray/Brown: Taillamps/Parking
Lamps .
White: Ground .
White/Green: Back-up Lamps .
Red/Green: Battery Feed .
Dark Blue: Trailer Brake

Black plate (82,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-82 Driving and Operating If the vehicle is equipped with the
heavy-duty trailering option, see
“ Heavy-Duty Trailer Wiring Harness
Package ” earlier in this section.
When the camper-wiring harness is
ordered without the heavy-duty
trailering package, a seven-wire
harness with a seven-pin connector
is at the rear of the vehicle and is
tied to the vehicle's frame.
Electric Brake Control Wiring
Provisions These wiring provisions are
included with the vehicle as part of
the trailer wiring package. These
provisions are for an electric brake
controller.
The harness should be installed by
your dealer or a qualified service
center. Tow/Haul Mode
Pressing this button at the end of
the shift lever turns on and off the
Tow/Haul Mode.
This indicator light on the instrument
cluster comes on when the Tow/
Haul Mode is on. Tow/Haul is a feature that assists
when pulling a heavy trailer or a
large or heavy load. See Tow/Haul
Mode on page 9-39 .
Tow/Haul is designed to be most
effective when the vehicle and
trailer combined weight is at least
75% of the vehicle's Gross
Combined Weight Rating (GCWR).
See “ Weight of the Trailer ” under
Trailer Towing on page 9-71 . Tow/
Haul is most useful under the
following driving conditions: .
When pulling a heavy trailer or a
large or heavy load through
rolling terrain. .
When pulling a heavy trailer or a
large or heavy load in
stop-and-go traffic. .
When pulling a heavy trailer or a
large or heavy load in busy
parking lots where improved low
speed control of the vehicle is
desired.