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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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248 Climate Controls
Manual Operation
O:Press to turn the climate control
system on or off. When off is
selected, the system will stop air
from flowing into the cabin. If on is
selected, any other button press
occurs, or a knob is turned, the
climate control system will turn on
and operate to the current setting.
9: Turn clockwise or
counterclockwise to increase or
decrease the fan speed. Press the
knob to turn the fan off.
Press AUTO to return to automatic
operation.
Driver and Passenger
Temperature Control : The
temperature can be adjusted
separately for the driver and
passenger.
Turn the knob clockwise or
counterclockwise to increase or
decrease the driver or passenger
temperature setting.
SYNC : Press to link the passenger
temperature setting to the driver
setting. The SYNC indicator light will turn on. When the passenger setting
is adjusted, the SYNC indicator light
is off.
The driver side or passenger side
temperature display shows the
temperature setting increasing or
decreasing.
Air Delivery Mode Control :
PressY,\,[, or-to change
the direction of the airflow. An
indicator light comes on in the
selected mode button.
Changing the mode cancels the
automatic operation and the system
goes into manual mode. Press
AUTO to return to automatic
operation.
Y: Air is directed to the instrument
panel outlets.
\: Air is divided between the
instrument panel and floor outlets.
Some air is directed toward the
windshield and side window outlets.
[: Air is directed to the floor
outlets, with some to the windshield,
side window outlets, and second
row floor outlets.
-: 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: 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 0250.
A/C : 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.
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@: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: 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
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,
press
Kto heat the mirrors. See
Heated Mirrors 048.
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.
Some vehicles may have the
exterior temperature sensor in the
passenger side mirror instead of the
front grille area.
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.
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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250 Climate Controls
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.
. Clear snow off the hood to
improve visibility and help
decrease moisture drawn into
the vehicle.
. Keep the path under the front
seats clear of objects to help
circulate the air inside of the
vehicle more effectively.
. Use of non-GM approved hood
deflectors can adversely affect
the performance of the system.
Check with your dealer before
adding equipment to the outside
of the vehicle.
Maintenance
Passenger Compartment
Air Filter
The filter reduces the dust, pollen,
and other airborne irritants from
outside air that is pulled into the
vehicle.
The filter should be replaced as part
of routine scheduled maintenance.
See Maintenance Schedule 0455.
To find out what type of filter to use,
see Maintenance Replacement
Parts 0466.
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1. Open the lower glove box doorcompletely.
2. Remove the four screws from around the lower glove box.
The door does not need to be
removed to access the screws.
3. Close the lower glove box doorand pull it from its frame to
remove the entire unit.
4. Release the two tabs holding
the service door. Open the
service door and remove the
old filter.
5. Install the new air filter.
6. Close the service door and secure the tabs.
7. Reverse the steps to reinstall the glove box.
See your dealer if additional
assistance is needed.
Service
All vehicles have a label underhood
that identifies the refrigerant used in
the vehicle. The refrigerant system
should only be serviced by trained
and certified technicians. The air
conditioning evaporator should
never be repaired or replaced by
one from a salvage vehicle.
It should only be replaced by a new
evaporator to ensure proper and
safe operation.
During service, all refrigerants
should be reclaimed with proper
equipment. Venting refrigerants
directly to the atmosphere is harmful
to the environment and may also
create unsafe conditions based on
inhalation, combustion, frostbite,
or other health-based concerns.
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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252 Driving and Operating
Driving and
Operating
Driving Information
Distracted Driving . . . . . . . . . . . . 253
Defensive Driving . . . . . . . . . . . . . 254
Drunk Driving . . . . . . . . . . . . . . . . . 254
Control of a Vehicle . . . . . . . . . . . 254
Braking . . . . . . . . . . . . . . . . . . . . . . . 254
Steering . . . . . . . . . . . . . . . . . . . . . . 255
Off-Road Recovery . . . . . . . . . . . 256
Loss of Control . . . . . . . . . . . . . . . 256
Off-Road Driving . . . . . . . . . . . . . 257
Driving on Wet Roads . . . . . . . . 261
Hill and Mountain Roads . . . . . 262
Winter Driving . . . . . . . . . . . . . . . . 263
If the Vehicle Is Stuck . . . . . . . . 264
Vehicle Load Limits . . . . . . . . . . . 265
Truck-Camper LoadingInformation . . . . . . . . . . . . . . . . . . 271
Starting and Operating
New Vehicle Break-In . . . . . . . . . 273
Adjustable Throttle and BrakePedal . . . . . . . . . . . . . . . . . . . . . . . 273
Ignition Positions . . . . . . . . . . . . . 274
Starting the Engine . . . . . . . . . . . 275
Fast Idle System . . . . . . . . . . . . . 276 Retained Accessory
Power (RAP) . . . . . . . . . . . . . . . . 277
Engine Coolant Heater . . . . . . . 278
Shifting Into Park . . . . . . . . . . . . . 279
Shifting out of Park . . . . . . . . . . . 280
Parking over Things That Burn . . . . . . . . . . . . . . . . . . . 281
Active Fuel Management . . . . . 281
Engine Exhaust
Engine Exhaust . . . . . . . . . . . . . . 282
Running the Vehicle While Parked . . . . . . . . . . . . . . . . . . . . . . 282
Automatic Transmission
Automatic Transmission . . . . . . 283
Manual Mode . . . . . . . . . . . . . . . . . 286
Tow/Haul Mode . . . . . . . . . . . . . . . 288
Drive Systems
Four-Wheel Drive . . . . . . . . . . . . . 289
Brakes
Antilock BrakeSystem (ABS) . . . . . . . . . . . . . . . 297
Parking Brake . . . . . . . . . . . . . . . . 297
Brake Assist . . . . . . . . . . . . . . . . . . 298
Hill Start Assist (HSA) . . . . . . . . 298
Ride Control Systems
Traction Control/Electronic Stability Control . . . . . . . . . . . . . 299 Hill Descent Control (HDC) . . . 301
Locking Rear Axle . . . . . . . . . . . . 302
Cruise Control
Cruise Control . . . . . . . . . . . . . . . . 302
Driver Assistance Systems
Driver Assistance Systems . . . 305
Assistance Systems for
Parking or Backing . . . . . . . . . . 306
Assistance Systems for Driving . . . . . . . . . . . . . . . . . . . . . . 308
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . . . . . . . 308
Forward Automatic Braking (FAB) . . . . . . . . . . . . . . . 310
Lane Departure Warning (LDW) (2500/3500
Series) . . . . . . . . . . . . . . . . . . . . . . 312
Lane Keep Assist (LKA) (1500 Series) . . . . . . . . . . . . . . . . . . . . . . 313
Fuel
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 315
California FuelRequirements . . . . . . . . . . . . . . . 316
Fuels in Foreign Countries . . . 316
Fuel Additives . . . . . . . . . . . . . . . . 316
E85 or FlexFuel . . . . . . . . . . . . . . 317
Filling the Tank . . . . . . . . . . . . . . . 317
Filling a Portable Fuel Container . . . . . . . . . . . . . . . . . . . 319
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Driving and Operating 253
Trailer Towing
General TowingInformation . . . . . . . . . . . . . . . . . . 320
Driving Characteristics and Towing Tips . . . . . . . . . . . . . . . . . 320
Trailer Towing . . . . . . . . . . . . . . . . 323
Towing Equipment . . . . . . . . . . . . 340
Trailer Sway Control (TSC) . . . 349
Conversions and Add-Ons
Add-On Electrical
Equipment . . . . . . . . . . . . . . . . . . 350
Adding a Snow Plow or Similar Equipment . . . . . . . . . . . . . . . . . . 350
Pickup Conversion to Chassis Cab . . . . . . . . . . . . . . . . 354
Driving Information
Distracted Driving
Distraction comes in many forms
and can take your focus from the
task of driving. Exercise good
judgment and do not let other
activities divert your attention away
from the road. Many local
governments have enacted laws
regarding driver distraction. Become
familiar with the local laws in
your area.
To avoid distracted driving, keep
your eyes on the road, keep your
hands on the steering wheel, and
focus your attention on driving.
. Do not use a phone in
demanding driving situations.
Use a hands-free method to
place or receive necessary
phone calls.
. Watch the road. Do not read,
take notes, or look up
information on phones or other
electronic devices. .
Designate a front seat
passenger to handle potential
distractions.
. Become familiar with vehicle
features before driving, such as
programming favorite radio
stations and adjusting climate
control and seat settings.
Program all trip information into
any navigation device prior to
driving.
. Wait until the vehicle is parked
to retrieve items that have fallen
to the floor.
. Stop or park the vehicle to tend
to children.
. Keep pets in an appropriate
carrier or restraint.
. Avoid stressful conversations
while driving, whether with a
passenger or on a cell phone.
{Warning
Taking your eyes off the road too
long or too often could cause a
crash resulting in injury or death.
Focus your attention on driving.
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254 Driving and Operating
Refer to the infotainment section for
more information on using that
system and the navigation system,
if equipped, including pairing and
using a cell phone.
Defensive Driving
Defensive driving means“always
expect the unexpected.” The first
step in driving defensively is to wear
the safety belt. See Safety Belts
0 65.
. Assume that other road users
(pedestrians, bicyclists, and
other drivers) are going to be
careless and make mistakes.
Anticipate what they might do
and be ready.
. Allow enough following distance
between you and the driver in
front of you.
. Focus on the task of driving.
Drunk Driving
Death and injury associated with
drinking and driving is a global
tragedy.
{Warning
Drinking and then driving is very
dangerous. Your reflexes,
perceptions, attentiveness, and
judgment can be affected by even
a small amount of alcohol. You
can have a serious —or even
fatal —collision if you drive after
drinking.
Do not drink and drive or ride with
a driver who has been drinking.
Ride home in a cab; or if you are
with a group, designate a driver
who will not drink.
Control of a Vehicle
Braking, steering, and accelerating
are important factors in helping to
control a vehicle while driving.
Braking
Braking action involves perception
time and reaction time. Deciding to
push the brake pedal is perception
time. Actually doing it is
reaction time. Average driver reaction time is
about three-quarters of a second. In
that time, a vehicle moving at
100 km/h (60 mph) travels 20 m
(66 ft), which could be a lot of
distance in an emergency.
Helpful braking tips to keep in mind
include:
.
Keep enough distance between
you and the vehicle in front
of you.
. Avoid needless heavy braking.
. Keep pace with traffic.
If the engine ever stops while the
vehicle is being driven, brake
normally but do not pump the
brakes. Doing so could make the
pedal harder to push down. If the
engine stops, there will be some
power brake assist but it will be
used when the brake is applied.
Once the power assist is used up, it
can take longer to stop and the
brake pedal will be harder to push.
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Steering
Electric Power Steering (1500
Series)
If the vehicle has electric power
steering, it does not have power
steering fluid. Regular maintenance
is not required.
If power steering assist is lost due
to a system malfunction, the vehicle
can be steered, but may require
increased effort. See your dealer if
there is a problem.
If the steering wheel is turned until it
reaches the end of its travel, and is
held in that position for an extended
period of time, power steering assist
may be reduced.
If the steering assist is used for an
extended period of time, power
assist may be reduced.
Normal use of the power steering
assist should return when the
system cools down.
See specific vehicle steering
messages underSteering System
Messages 0163.
Hydraulic Power Steering
(2500/3500 Series)
(2500/3500 Series –All Regular
Cab, Double Cab/Crew Cab
without Digital Steer Assist)
The power steering system may
require maintenance.
See Power Steering Fluid (1500
Series) 0379 orPower Steering
Fluid (2500/3500 Series) 0379.
If power steering assist is lost
because the engine stops or the
system malfunctions, the vehicle
can be steered but may require
increased effort. See your dealer.
(2500/3500 Series –Double Cab/
Crew Cab with Digital Steer
Assist)
The vehicle has a Digital Steer
Assist power steering system that
varies the amount of effort required
to steer the vehicle. Less steering
effort is required at slower speeds.
At faster speeds, the steering effort
increases. The system helps the
steering wheel return to center at
low speeds. Pressing the Tow/Haul button adjusts steering effort for
driving conditions described in
Tow/
Haul Mode 0288.
The power steering system may
require maintenance.
See Power Steering Fluid (1500
Series) 0379 orPower Steering
Fluid (2500/3500 Series) 0379.
If power steering assist is lost
because the engine stops or the
system malfunctions, the vehicle
can be steered but may require
increased effort. See your dealer.
Caution
If the steering wheel is turned
until it reaches the end of its
travel, and is held in that position
for more than 15 seconds,
damage may occur to the power
steering system and there may be
loss of power steering assist.