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Driving and Operating 217
near a strong radio antenna signal causing
interference to the Keyless Access system.
SeeRemote Key Operation 015.
To shift out of P (Park), the vehicle must be
on and the brake pedal must be applied.
{Warning
Turning 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.
Stopping the Engine/LOCK/OFF (No Indicator
Lights) : When the vehicle is stopped, press
ENGINE START/STOP once to turn the
engine off.
If the vehicle is in P (Park), the vehicle will
turn off, and Retained Accessory Power (RAP)
will remain active. See Retained Accessory
Power (RAP) 0220.
If the vehicle is not in P (Park), the vehicle
will return to accessory mode and display
the message SHIFT TO PARK in the Driver
Information Center (DIC). When the vehicle is
shifted into P (Park), the vehicle will turn off. The vehicle may have an electric steering
column lock. The lock is activated when the
ignition is turned off and driver door is
opened. A sound may be heard as the lock
actuates or releases. The steering column
lock may not release with the wheels turned
off center. If this happens, the vehicle may
not start. Move the steering wheel from left
to right while attempting to start the
vehicle. If this does not work, the vehicle
needs service.
Unless an emergency exists, do 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. If the vehicle cannot be pulled over, and must be shut off while driving, press and
hold ENGINE START/STOP button for
longer than two seconds, or press twice
in five seconds.
2. Brake using a firm and steady pressure. Do not pump the brakes repeatedly. This
may deplete power assist, requiring
increased brake pedal force. 3. 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.
4. Come to a complete stop, shift to P (Park), and make sure engine is off.
The shift lever must be in P (Park) to
turn the vehicle off.
5. Set the parking brake. See Electric
Parking Brake 0234.
{Warning
Turning 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.
Accessory Mode (Amber Indicator Light) :
This mode allows some electrical accessories
to be used when the engine is off.
With the vehicle off, pressing the ENGINE
START/STOP button one time without the
brake pedal applied will place the vehicle in
accessory mode.

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218 Driving and Operating
The vehicle will switch from accessory mode
to off after five minutes to prevent battery
rundown.
ON/RUN/START (Green Indicator Light) :This
mode is for driving and starting. With the
vehicle off, and the brake pedal applied,
pressing ENGINE START/STOP button once
will turn the ignition on. Once engine
cranking begins, release the button. Engine
cranking will continue until the engine
starts. See Starting the Engine 0218.
Service Mode
This power mode is available for service and
diagnostics, and to verify the proper
operation of the malfunction indicator lamp
as may be required for emission inspection
purposes. With the vehicle off, and the
brake pedal not applied, pressing and
holding the ENGINE START/STOP button for
more than five seconds will place the vehicle
in Service Mode. The instruments and audio
systems will operate as they do when the
vehicle is on, but the vehicle will not be able
to be driven. The engine will not start in
Service Mode. Press the ENGINE START/STOP
button again to turn the vehicle off.Starting the Engine
If the vehicle has a diesel engine, see the
Duramax diesel supplement.
Caution
If you add electrical parts or accessories,
you could change the way the engine
operates. Any resulting damage would
not be covered by the vehicle warranty.
See Add-On Electrical Equipment 0306.
Move the shift lever to P (Park) or
N (Neutral). To restart the engine when the
vehicle is already moving, use
N (Neutral) only.
Caution
Do not try to shift to P (Park) if the
vehicle is moving. If you do, you could
damage the transmission. Shift to P (Park)
only when the vehicle is stopped.
Starting Procedure
1. The remote key must be in the vehicle. Press ENGINE START/STOP with the brake
pedal applied. When the engine begins
cranking, let go of the button. The driver may observe a minor, and
temporary, brake pedal kickback when
starting the vehicle. This is normal.
The idle speed will go down as the
engine gets warm. Do not race the
engine immediately after starting it.
Operate the engine and transmission
gently to allow the oil to warm up and
lubricate all moving parts.
When the low fuel warning light is on
and the FUEL LEVEL LOW message is
displayed in the Driver Information
Center (DIC), press ENGINE START/STOP
to continue engine cranking.
Caution
Cranking the engine for long periods of
time, by returning the ignition to the
START position immediately after
cranking has ended, can overheat and
damage the cranking motor, and drain
the battery. Wait at least 15 seconds
between each try, to let the cranking
motor cool down.
2. If the engine does not start after five to 10 seconds, especially in very cold
weather (below −18 °C or 0 °F), it could
be flooded with too much gasoline. Try

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234 Driving and Operating
If there is a problem with ABS, this warning
light stays on. SeeAntilock Brake System
(ABS) Warning Light 0125.
ABS does not change the time needed to
get a foot on the brake pedal and does not
always decrease stopping distance. If you
get too close to the vehicle ahead, there will
not be enough time to apply the brakes if
that vehicle suddenly slows or stops. Always
leave enough room ahead to stop, even
with ABS.
Using ABS
Do not pump the brakes. Just hold the brake
pedal down firmly. Hearing or feeling ABS
operate is normal.
Braking in Emergencies
ABS allows steering and braking at the same
time. In many emergencies, steering can
help even more than braking.
Electric Parking Brake
Work Truck Shown, Others Similar
The Electric Parking Brake (EPB) can always
be applied, even if the vehicle is off. In the
case of insufficient electrical power,
however, the EPB cannot be applied or
released. To prevent draining the battery,
avoid unnecessary repeated cycles of
the EPB.
The system has a red parking brake status
light and an amber service parking brake
warning light. See Electric Parking Brake
Light 0124 and
Service Electric Parking Brake Light 0124.
There are also parking brake-related Driver
Information Center (DIC) messages. Before leaving the vehicle, check the red
parking brake status light to ensure that the
parking brake is applied.
EPB Apply
To apply the EPB:
1. Be sure the vehicle is at a complete stop.
2. Press the EPB switch momentarily.
The red parking brake status light will flash
and then stay on once the EPB is fully
applied. If the red parking brake status light
flashes continuously, then the EPB is only
partially applied or there is a problem with
the EPB. A DIC message will display. Release
the EPB and try to apply it again. If the
light does not come on, or keeps flashing,
have the vehicle serviced. Do not drive the
vehicle if the red parking brake status light
is flashing. See your dealer.
If the amber service parking brake warning
light is on, press the EPB switch. Continue to
hold the switch until the red parking brake
status light remains on. If the amber service
parking brake warning light is on, see your
dealer.

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236 Driving and Operating
HSA is available when the vehicle is facing
uphill in a forward gear, or when facing
downhill in R (Reverse). The vehicle must
come to a complete stop on a grade for HSA
to activate.
Ride Control Systems
Traction Control/Electronic
Stability Control
System Operation
The vehicle has a Traction Control System
(TCS) and StabiliTrak/Electronic Stability
Control (ESC) system. These systems help
limit wheel spin and assist the driver in
maintaining control, especially on slippery
road conditions.
TCS activates if it senses any of the drive
wheels are spinning or beginning to lose
traction. When this happens, TCS applies the
brakes to the spinning wheels and reduces
engine power to limit wheel spin.
StabiliTrak/ESC activates when the vehicle
senses a difference between the intended
path and the direction the vehicle is actually
traveling. StabiliTrak/ESC selectively applies
braking pressure to any one of the vehicle
wheel brakes to assist the driver in keepingthe vehicle on the intended path. Trailer
Sway Control (TSC) is also on automatically
when the vehicle is started. See
Trailer Sway
Control (TSC) 0294.
If cruise control is being used and traction
control or StabiliTrak/ESC 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 0209 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,
gcomes on, and
the appropriate message will appear on the Driver Information Center (DIC). Both
traction control and StabiliTrak/ESC 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/ESC 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
dcomes 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
dcomes on and stays on:
1. Stop the vehicle.
2. Turn the engine off and wait 15 seconds.
3. Start the engine.

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Driving and Operating 253
Cleaning
Depending on vehicle options, keep these
areas of the vehicle clean to ensure the best
driver assistance feature performance. Driver
Information Center (DIC) messages may
display when the systems are unavailable or
blocked.
.Front and rear bumpers and the area
below the bumpers
.Front grille and headlamps
.Front camera lens in the front grille or
near the front emblem
.Front side and rear side panels
.Outside of the windshield in front of the
rearview mirror
.Side camera lens on the bottom of the
outside mirrors
.Rear side corner bumpers
.Rear Vision Camera in the tailgate handle
.Rear Camera Mirror and Cargo View
Camera in the Center High-Mounted
StoplampRadio Frequency
This vehicle may be equipped with driver
assistance systems that operate using radio
frequency. See
Radio Frequency Statement
0 413.
Assistance Systems for Parking or
Backing
If equipped, the Rear Vision Camera (RVC),
Surround Vision, Rear Park Assist (RPA),
Front Park Assist (FPA), and Rear Cross
Traffic Alert (RCTA) may help the driver park
or avoid objects. Always check around the
vehicle when parking or backing.
The RVC, RPA, and Surround Vision 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 infotainment
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 any button on the
infotainment system, shift into P (Park), or,

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262 Driving and Operating
.The accessory trailer cameras were
plugged in when the vehicle was running.
The vehicle needs to be off, with all doors
closed, for at least five minutes prior to
plugging in a trailer camera.
A view may switch automatically if:
.The vehicle is shifted to another gear.
Park Assist
The vehicle may be equipped with Rear Park
Assist (RPA) or Front and Rear Park Assist
(FRPA). Under certain conditions, the Park
Assist system can assist the driver as the
vehicle moves at speeds of less than 8 km/h
(5 mph). The sensors on the bumpers may
detect objects up to 1.2 m (4 ft) in front and
1.8 m (6 ft) behind 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 Park 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 Park Assist, always check the area
around the vehicle and check all mirrors
before moving forward or backing.
The instrument cluster may have a Park
Assist display with bars that show “distance
to object” and object location information
for the Front and Rear Park Assist system.
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 around the
vehicle, one beep will be heard from the
front or rear (depending on the object's
location), or the driver's seat will pulse two
times if equipped with Safety Alert Seat.
When the object is very close to the vehicle,
the beeps will be continuous or the driver's
seat will pulse five times. Beeps in the front
are higher pitched than beeps in the rear.
Turning the Features On or Off
PressXon the center stack to turn on or
off the Front and Rear Park Assist. The
indicator light next to the button comes on
when the features are on and turns off
when the features have been disabled.
Front and Rear Park Assist can be turned
Off, On, or On with Towbar. To view
available settings from the infotainment
screen, touch Settings > Vehicle > Comfort
and Convenience. If Park Assist is turned off
through vehicle personalization, the Park
Assist button will be disabled. To turn Park

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Driving and Operating 265
shows the current setting on the DIC.
Additional button presses will change this
setting. The chosen setting will remain until
it is changed and will affect the timing of
both the Collision Alert and the Tailgating
Alert features. The timing of both alerts will
vary based on vehicle speed. The faster the
vehicle speed, the farther away the alert will
occur. Consider traffic and weather
conditions when selecting the alert timing.
The range of selectable alert timings may
not be appropriate for all drivers and driving
conditions.
If your vehicle is equipped with Adaptive
Cruise Control (ACC), changing the FCA
timing setting automatically changes the
following gap setting (Far, Medium,
or Near).
Following Distance Indicator
If equipped, the following distance to a
moving vehicle ahead in your path is
indicated in following time in seconds on
the Driver Information Center (DIC). See
Driver Information Center (DIC) (Base Level)
0131 or
Driver Information Center (DIC) (Uplevel)
0 133. The minimum following time is
0.5 seconds away. If there is no vehicle detected ahead, or the
vehicle ahead is out of sensor range, dashes
will be displayed.
Unnecessary Alerts
FCA may provide unnecessary alerts for
turning vehicles, vehicles in other lanes,
objects that are not vehicles, or shadows.
These alerts are normal operation and the
vehicle does not need service.
Cleaning the System
If the FCA system does not seem to operate
properly, this may correct the issue:
.Clean the outside of the windshield in
front of the rearview mirror.
.Clean the entire front of the vehicle.
.Clean the headlamps.
Automatic Emergency
Braking (AEB)
If equipped, AEB may help avoid or reduce
the harm caused by front-end crashes. AEB
also includes Intelligent Brake Assist (IBA).
When the system detects a vehicle ahead in
your path that is traveling in the same
direction that you may be about to crash
into, it can provide a boost to braking or
automatically brake the vehicle. This canhelp avoid or lessen the severity of crashes
when driving in a forward gear. Depending
on the situation, the vehicle may
automatically brake moderately or hard. This
automatic emergency braking can only occur
if a vehicle is detected. This is shown by the
FCA vehicle ahead indicator being lit. See
Forward Collision Alert (FCA) System
0263.
The system works when driving in a forward
gear between 8 km/h (5 mph) and 80 km/h
(50 mph). It can detect vehicles up to
approximately 60 m (197 ft).
{Warning
AEB is an emergency crash preparation
feature and is not designed to avoid
crashes. Do not rely on AEB to brake the
vehicle. AEB will not brake outside of its
operating speed range and only responds
to detected vehicles.
AEB may not:
.Detect a vehicle ahead on winding or
hilly roads.
.Detect all vehicles, especially vehicles
with a trailer, tractors, muddy
vehicles, etc. (Continued)

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282 Driving and Operating
The GCWR can also be confirmed by
weighing the truck and trailer on a public
scale. The truck and trailer should be loaded
for the trip with passengers and cargo.
Gross Combined Weight (GCW) Alert
If equipped, the GCW Alert can display a
message in the Driver Information Center
(DIC), indicating that the estimated
combined weight of the vehicle and trailer
may exceed the vehicle’s GCWR, under
certain circumstances. See“Gross Combined
Weight Rating” above. The vehicle does not
actually measure the loaded weight of your
vehicle or trailer. It uses vehicle data to
estimate these weights after you begin
a trip. The alert will not activate unless:
.The feature is turned on in the trailering
application. See
Trailering App0296.
.The vehicle-trailer combination have been
used enough together for the software to
estimate the combined vehicle and trailer
weight.
.The estimated weight could exceed the
vehicle’s maximum GCWR.
If the GCW alert message is displayed, stop
the vehicle when it is safe and check the
vehicle and trailer weight using a scale. See
“Maximum Trailer Weight” below.
{Warning
Always determine the actual weights of
the loaded vehicle and trailer using a
vehicle scale before beginning a trip.
Never use the GCW Alert to determine
whether the vehicle and trailer are
properly loaded or overloaded. Do not
drive with an overloaded vehicle or
trailer. Death, serious injury, or property
damage could occur.
GCWR is only one of the maximum weight
ratings applicable to your vehicle and trailer.
The GCW Alert does not estimate whether the vehicle alone exceeds the GVWR, the
rear-axle weight exceeds GAWR-RR, the
trailer exceeds the Maximum Trailer Weight
Rating or the trailer tongue weight exceeds
the Maximum Tongue Weight Rating.
Always verify that the weight of the vehicle,
vehicle contents, trailer, trailer contents and
trailer tongue are below all of these
maximum weight ratings. See
“Maximum
Trailer Weight” below.
Gross Vehicle Weight Rating (GVWR)
For information about the vehicle's
maximum load capacity, see Vehicle Load
Limits 0210. When calculating the GVWR
with a trailer attached, the trailer tongue
weight must be included as part of the
weight the vehicle is carrying.
Maximum Trailer Weight
The maximum trailer weight rating is
calculated assuming the tow vehicle has a
driver, a front seat passenger, and all
required trailering equipment. This value
represents the heaviest trailer the vehicle
can tow, but it may be necessary to reduce
the trailer weight to stay within the GCWR,
GVWR, maximum trailer tongue load,
or GAWR-RR for the vehicle.