lock GMC SIERRA DENALI 2015 Repair Manual

Black plate (3,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Climate Controls 8-3Changing the mode cancels the
automatic operation and the system
goes into manual mode. Press
AUTO to return to automatic
operation.
Y (Vent): Air is directed to the
instrument panel outlets.
\ (Bi-Level): Air is divided
between the instrument panel and
floor outlets. Some air is directed
toward the windshield and side
window outlets.
[ (Floor): Air is directed to the
floor outlets, with some to the
windshield, side window outlets, and
second row floor outlets.
- (Defog): This mode clears the
windows of fog or moisture. Air is
directed to the windshield, floor
outlets, and side window vents. The
system automatically forces outside
air into the vehicle and the air
conditioning compressor will run,
unless the outside temperature is
close to freezing. 0 (Defrost): Press to clear the
windshield of fog or frost more
quickly. Air is directed to the
windshield and the side window
vents. The air conditioning
compressor also comes on, unless
the outside temperature is below
freezing.
Do not drive the vehicle until all
windows are clear.
See Air Vents on page 8-4 .
A/C (Air Conditioning): Press to
turn the air conditioning system on
or off. An indicator light comes on to
show that the air conditioning is
enabled. If the fan is turned off, the
air conditioner will not run. The A/C
light will stay on even if the outside
temperatures are below freezing.
@ (Recirculation): Press to turn
on recirculation. An indicator light
comes on. Air is recirculated to
quickly cool the inside of the
vehicle. It can also be used to help
reduce outside air and odors that enter the vehicle. The air
conditioning compressor also comes
on when this mode is activated.
Rear Window Defogger The rear window defogger uses a
warming grid to remove fog from the
rear window.
K (Rear Window Defogger):
Press to turn the rear window
defogger on or off. An indicator light
on the button comes on to show that
the rear window defogger is on.
The rear window defogger only
works when the ignition is in ON/
RUN. The defogger turns off if the
ignition is turned to ACC/
ACCESSORY or LOCK/OFF.
{ Caution
Using a razor blade or sharp
object to clear the inside rear
window can damage the rear
window defogger. Repairs would
(Continued)

Black plate (4,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
8-4 Climate Controls Caution (Continued)not be covered by the vehicle
warranty. Do not clear the inside
rear window with sharp objects.
Heated Mirror: If equipped with
heated outside rearview mirrors, the
mirrors heat to help clear fog or frost
from the surface of the mirror when
the rear window defog button is
pressed. See Heated Mirrors on
page 2-17 .
Sensors The solar sensor, located in the
defrost grille in the middle of the
instrument panel, monitors the solar
heat. Do not cover the solar sensor
or the system will not work properly.
There is also an exterior
temperature sensor behind the front
grille. This sensor reads the outside
air temperature and helps maintain
the temperature inside the vehicle.
Any cover on the front of the vehicle
including a snow plow, could cause
a false reading in the displayed
temperature.
The climate control system uses the
information from these sensors to
maintain comfort settings by
adjusting the outlet temperature, fan
speed, and the air delivery mode.
The system may also supply cooler
air to the side of the vehicle facing
the sun. The recirculation mode will
also be used as needed to maintain
cool outlet temperatures. Air Vents Use the air vents in the center and
on the side of the instrument panel
to direct airflow. Use the
thumbwheels near the air vents to
open or close off the airflow.
Air vents blow warm air on the side
windows in cold weather. If Floor,
Defog, or Defrost modes are
selected, a small amount of air will
come from the vents close to the
window. If the airflow is shut off
using the thumbwheels, warm air
will be directed to the other
instrument panel vents. This is
normal operation.
Use the thumbwheels to turn vent
airflow on or off based on the mode
selected.
Operation Tips .
Clear away any ice, snow,
or leaves from air inlets at the
base of the windshield that could
block the flow of air into the
vehicle.

Black plate (1,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-1
Driving and
Operating Driving Information Distracted Driving . . . . . . . . . . . . . 9-2
Defensive Driving . . . . . . . . . . . . . 9-3
Drunk Driving . . . . . . . . . . . . . . . . . 9-3
Control of a Vehicle . . . . . . . . . . . 9-3
Braking . . . . . . . . . . . . . . . . . . . . . . . 9-3
Steering . . . . . . . . . . . . . . . . . . . . . . . 9-4
Off-Road Recovery . . . . . . . . . . . . 9-5
Loss of Control . . . . . . . . . . . . . . . . 9-5
Off-Road Driving . . . . . . . . . . . . . . 9-6
Driving on Wet Roads . . . . . . . . 9-11
Hill and Mountain Roads . . . . . 9-11
Winter Driving . . . . . . . . . . . . . . . 9-12
If the Vehicle Is Stuck . . . . . . . . 9-14
Vehicle Load Limits . . . . . . . . . . 9-15
Truck-Camper Loading
Information . . . . . . . . . . . . . . . . . 9-21
Starting and Operating New Vehicle Break-In . . . . . . . . 9-23
Adjustable Throttle and Brake
Pedal . . . . . . . . . . . . . . . . . . . . . . . 9-23
Ignition Positions . . . . . . . . . . . . 9-24
Starting the Engine . . . . . . . . . . 9-26 Fast Idle System . . . . . . . . . . . . . 9-27
Engine Heater . . . . . . . . . . . . . . . 9-28
Retained Accessory
Power (RAP) . . . . . . . . . . . . . . . 9-29
Shifting Into Park . . . . . . . . . . . . 9-30
Shifting out of Park . . . . . . . . . . 9-31
Parking over Things
That Burn . . . . . . . . . . . . . . . . . . 9-32
Active Fuel Management ®
. . . 9-32
Engine Exhaust Engine Exhaust . . . . . . . . . . . . . . 9-32
Running the Vehicle While
Parked . . . . . . . . . . . . . . . . . . . . . 9-33
Automatic Transmission Automatic Transmission . . . . . 9-33
Manual Mode . . . . . . . . . . . . . . . . 9-36
Tow/Haul Mode . . . . . . . . . . . . . . 9-39
Drive Systems Four-Wheel Drive . . . . . . . . . . . . 9-40
Brakes Antilock Brake
System (ABS) . . . . . . . . . . . . . . 9-46
Parking Brake . . . . . . . . . . . . . . . 9-47
Brake Assist . . . . . . . . . . . . . . . . . 9-48
Hill Start Assist (HSA) . . . . . . . 9-48 Ride Control Systems Traction Control/Electronic
Stability Control . . . . . . . . . . . . 9-49
Hill Descent
Control (HDC) . . . . . . . . . . . . . . 9-51
Locking Rear Axle . . . . . . . . . . . 9-52
Cruise Control Cruise Control . . . . . . . . . . . . . . . 9-52
Driver Assistance Systems Driver Assistance
Systems . . . . . . . . . . . . . . . . . . . . 9-55
Assistance Systems for
Parking or Backing . . . . . . . . . 9-56
Assistance Systems for
Driving . . . . . . . . . . . . . . . . . . . . . 9-59
Forward Collision Alert (FCA)
System . . . . . . . . . . . . . . . . . . . . . 9-59
Lane Departure
Warning (LDW) . . . . . . . . . . . . . 9-61
Fuel Fuel . . . . . . . . . . . . . . . . . . . . . . . . . 9-63
California Fuel
Requirements . . . . . . . . . . . . . . 9-64
Fuels in Foreign Countries . . . 9-64
Fuel Additives . . . . . . . . . . . . . . . 9-64

Black plate (5,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-5.
Wait until the vehicle is out of
the curve before accelerating
gently into the straightaway.
Steering in Emergencies .
There are some situations when
steering around a problem may
be more effective than braking. .
Holding both sides of the
steering wheel allows you to turn
180 degrees without removing
a hand. .
Antilock Brake System (ABS)
allows steering while braking. Off-Road Recovery
The vehicle's right wheels can drop
off the edge of a road onto the
shoulder while driving. Follow
these tips:
1. Ease off the accelerator and
then, if there is nothing in the
way, steer the vehicle so that it
straddles the edge of the
pavement.
2. Turn the steering wheel about
one-eighth of a turn, until the
right front tire contacts the
pavement edge. 3. Turn the steering wheel to go
straight down the roadway.
Loss of Control Skidding There are three types of skids that
correspond to the vehicle's three
control systems: .
Braking Skid — wheels are not
rolling. .
Steering or Cornering Skid —
too much speed or steering in a
curve causes tires to slip and
lose cornering force. .
Acceleration Skid — too much
throttle causes the driving
wheels to spin.
Defensive drivers avoid most skids
by taking reasonable care suited to
existing conditions, and by not
overdriving those conditions. But
skids are always possible.

Black plate (6,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-6 Driving and Operating If the vehicle starts to slide, follow
these suggestions: .
Ease your foot off the
accelerator pedal and steer the
way you want the vehicle to go.
The vehicle may straighten out.
Be ready for a second skid if it
occurs. .
Slow down and adjust your
driving according to weather
conditions. Stopping distance
can be longer and vehicle
control can be affected when
traction is reduced by water,
snow, ice, gravel, or other
material on the road. Learn to
recognize warning clues — such
as enough water, ice, or packed
snow on the road to make a
mirrored surface — and slow
down when you have any doubt. .
Try to avoid sudden steering,
acceleration, or braking,
including reducing vehicle speed
by shifting to a lower gear. Any
sudden changes could cause
the tires to slide. Remember: Antilock brakes help
avoid only the braking skid.
Off-Road Driving Four-wheel-drive vehicles can be
used for off-road driving. Vehicles
without four-wheel drive and
vehicles not equipped with All
Terrain (AT) or On-Off Road (OOR)
tires must not be driven off-road
except on a level, solid surface. For
contact information about the
original equipment tires, see the
warranty manual.
One of the best ways for successful
off-road driving is to control the
speed.
{ Warning
When driving off-road, bouncing
and quick changes in direction
can easily throw you out of
position. This could cause you to
lose control and crash. You and
your passengers should always
wear safety belts. Before Driving Off-Road .
Have all necessary maintenance
and service work completed. .
Fuel the vehicle, fill fluid levels,
and check inflation pressure in
all tires, including the spare,
if equipped. .
Read all the information about
four-wheel-drive vehicles in this
manual. .
Remove any underbody air
deflector, if equipped. Re-attach
the air deflector after off-road
driving. .
See Hill Descent Control (HDC)
on page 9-51 .
Know the local laws that apply to
off-road driving.
To gain more ground clearance if
needed, it may be necessary to
remove the front fascia lower air
dam. However, driving without the
air dam reduces fuel economy.

Black plate (12,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-12 Driving and Operating .
Check all fluid levels and brakes,
tires, cooling system, and
transmission. .
Shift to a lower gear when going
down steep or long hills.
{ WarningUsing the brakes to slow the
vehicle on a long downhill slope
can cause brake overheating, can
reduce brake performance, and
could result in a loss of braking.
Shift the transmission to a lower
gear to let the engine assist the
brakes on a steep downhill slope.
{ Warning
Coasting downhill in N (Neutral)
or with the ignition off is
dangerous. This can cause
overheating of the brakes and
(Continued) Warning (Continued) loss of steering. Always have the
engine running and the vehicle
in gear. .
Stay in your own lane. Do not
swing wide or cut across the
center of the road. Drive at
speeds that let you stay in your
own lane. .
Be alert on top of hills;
something could be in your lane
(stalled car, accident). .
Pay attention to special road
signs (falling rocks area, winding
roads, long grades, passing or
no-passing zones) and take
appropriate action.
Winter Driving Driving on Snow or Ice
Drive carefully when there is snow
or ice between the tires and the
road, creating less traction or grip. Wet ice can occur at about 0°C
(32°F) when freezing rain begins to
fall, resulting in even less traction.
Avoid driving on wet ice or in
freezing rain until roads can be
treated with salt or sand.
Drive with caution, whatever the
condition. Accelerate gently so
traction is not lost. Accelerating too
quickly causes the wheels to spin
and makes the surface under the
tires slick, so there is even less
traction.
Traction Control should be turned
on. See Traction Control/Electronic
Stability Control on page 9-49 .
The Antilock Brake System (ABS)
improves vehicle stability during
hard stops on slippery roads, but
apply the brakes sooner than when
on dry pavement. See Antilock
Brake System (ABS) on page 9-46 .
Allow greater following distance on
any slippery road and watch for
slippery spots. Icy patches can
occur on otherwise clear roads in
shaded areas. The surface of a

Black plate (13,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-13curve or an overpass can remain icy
when the surrounding roads are
clear. Avoid sudden steering
maneuvers and braking while
on ice.
Turn off cruise control on slippery
surfaces.
Blizzard Conditions Being stuck in snow can be a
serious situation. Stay with the
vehicle unless there is help nearby.
If possible, use Roadside
Assistance. See Roadside
Assistance Program on page 13-5 .
To get help and keep everyone in
the vehicle safe: .
Turn on the hazard warning
flashers. .
Tie a red cloth to an outside
mirror. { WarningSnow can trap engine exhaust
under the vehicle. This may
cause exhaust gases to get
inside. Engine exhaust contains
carbon monoxide (CO) which
cannot be seen or smelled. It can
cause unconsciousness and even
death.
If the vehicle is stuck in the snow: .
Clear away snow from around
the base of your vehicle,
especially any that is blocking
the exhaust pipe. .
Check again from time to
time to be sure snow does
not collect there. .
Open a window about 5 cm
(2 in) on the side of the
vehicle that is away from the
wind to bring in fresh air.
(Continued) Warning (Continued) .
Fully open the air outlets on
or under the instrument
panel. .
Adjust the climate control
system to a setting that
circulates the air inside the
vehicle and set the fan speed
to the highest setting. See
“ Climate Control Systems ” .
For more information about
carbon monoxide, see Engine
Exhaust on page 9-32 .
To save fuel, run the engine for only
short periods as needed to warm
the vehicle and then shut the engine
off and close the window most of
the way to save heat. Repeat this
until help arrives but only when you
feel really uncomfortable from the
cold. Moving about to keep warm
also helps.

Black plate (16,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-16 Driving and Operating open, you will find the label
attached below the door lock
post (striker). The Tire and
Loading Information label shows
the number of occupant seating
positions (1), and the maximum
vehicle capacity weight (2) in
kilograms and pounds.
The Tire and Loading
Information label also shows the
size of the original equipment
tires (3) and the recommended
cold tire inflation pressures (4).
For more information on tires
and inflation see Tires on
page 10-50 and Tire Pressure
on page 10-59 .
There is also important loading
information on the vehicle
Certification/Tire label. It tells
you the Gross Vehicle Weight
Rating (GVWR) and the Gross
Axle Weight Rating (GAWR) for the front and rear axles. See
“ Certification/Tire Label ” later in
this section. “ Steps for Determining Correct
Load Limit –
1.
Locate the statement "The
combined weight of
occupants and cargo should
never exceed XXX kg or
XXX lbs." on your vehicle ’ s
placard. 2.
Determine the combined
weight of the driver and
passengers that will be riding
in your vehicle. 3.
Subtract the combined
weight of the driver and
passengers from XXX kg or
XXX lbs.
4.
The resulting figure equals
the available amount of cargo
and luggage load capacity.
For example, if the "XXX"
amount equals 1400 lbs. and there will be five 150 lb
passengers in your vehicle,
the amount of available cargo
and luggage load capacity is
650 lbs. (1400-750 (5 x 150)
= 650 lbs.) 5.
Determine the combined
weight of luggage and cargo
being loaded on the vehicle.
That weight may not safely
exceed the available cargo
and luggage load capacity
calculated in Step 4. 6.
If your vehicle will be towing
a trailer, load from your trailer
will be transferred to your
vehicle. Consult this manual
to determine how this
reduces the available cargo
and luggage load capacity of
your vehicle. ”
See Trailer Towing on page 9-71
for important information on
towing a trailer, towing safety
rules, and trailering tips.

Black plate (24,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-24 Driving and Operating No adjustment to the pedals can be
made when the vehicle is in
R (Reverse) or while using cruise
control.
The switch used to adjust the
pedals is on the center stack, below
the climate controls.
Lift the switch up to move the
pedals closer to your body. Press
the switch down to move the
pedals away. Before you start driving, fully press
the brake pedal to confirm the
adjustment is right for you. While
driving, make only small
adjustments.
The vehicle may have a memory
function, which lets pedal settings
be saved and recalled. See Memory
Seats on page 3-5 .
Ignition Positions
Vehicles with Key Access have an
ignition switch with four different
positions. To shift out of P (Park), the ignition
must be in ON/RUN or ACC/
ACCESSORY and the regular brake
pedal must be applied.
1 (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 9-29 .
This position locks the ignition and
steering wheel. It also locks the
transmission on automatic
transmission vehicles. 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.

Black plate (25,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-25Do 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 9-47 .
{ 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.
{ Caution
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. 2 (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.
3 (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.
The switch stays in this position
when the engine is running. The
transmission is also unlocked in this
position on automatic transmission
vehicles.
If the key is left in the ACC/
ACCESSORY or ON/RUN position
with the engine off, the battery could
be drained. The vehicle may not
start if the battery is allowed to drain
for an extended period of time.