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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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216 Driving and Operating exceed the truck's cargo weight
rating, and the camper's center
of gravity (1) should fall within
the truck's recommended center
of gravity zone (2) when
installed.
Any accessories or other
equipment that are added to the
vehicle must be weighed. Then,
subtract this extra weight from
the CWR. This extra weight may
shorten the center of gravity
zone of the vehicle.
If the slide-in camper and its
load weighs less than the CWR,
the center of gravity zone for the
vehicle may be larger.
Secure loose items to prevent
weight shifts that could affect the
balance of the vehicle. When the
truck-camper is loaded, drive to
a scale and weigh on the front
and on the rear wheels
separately to determine axle
loads. Individual axle loads
should not exceed either of the gross axle weight ratings
(GAWR). The total axle
loads should not exceed the
vehicle's gross vehicle weight
rating (GVWR). These ratings
are given on the Certification/
Tire label attached to the
B-pillar. See “ Certification/Tire
Label ” under Vehicle Load
Limits 0 209 . If weight ratings
are exceeded, move or remove
items to bring all weights below
the ratings.
See your dealer for more
information on curb weights,
cargo weights, Cargo Weight
Rating, and the correct center of
gravity zone. Starting and
Operating New Vehicle Break-In CautionThe vehicle does not need an
elaborate break-in. But it will
perform better in the long run if
you follow these guidelines:
.
Keep the vehicle speed at
88 km/h (55 mph) or less for
the first 805 km (500 mi).
.
Do not drive at any one
constant speed, fast or slow,
for the first 805 km (500 mi).
Do not make full-throttle
starts. Avoid downshifting to
brake or slow the vehicle.
.
Avoid making hard stops for
the first 322 km (200 mi) or
so. During this time the new
brake linings are not yet
broken in. Hard stops with
new linings can mean
(Continued)
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Driving and Operating 217Caution (Continued) premature wear and earlier
replacement. Follow this
breaking-in guideline every
time you get new brake
linings.
.
Do not tow a trailer during
break-in. See Trailer Towing
0 281 for the trailer towing
capabilities of the vehicle
and more information.
Following break-in, engine speed
and load can be gradually
increased. Ignition Positions (Key
Access)
0. Stopping the Engine/LOCK/OFF
1. ACC/ACCESSORY
2. ON/RUN
3. START
The ignition switch has four
positions.
To shift out of P (Park), with an
automatic transmission, the ignition
must be ON/RUN and the brake
pedal must be applied. 0 (Stopping the Engine/LOCK/
OFF) : This position turns off the
vehicle. It also locks the ignition, the
transmission on an automatic
transmission vehicle, and the
steering column, if equipped with a
locking steering column.
To turn off the vehicle:
1. Make sure that the vehicle is
stopped.
2. Shift to P (Park) with an
automatic transmission,
or Neutral with a manual
transmission.
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
218 Driving and Operating 3. Continue to hold the brake
pedal, then set the parking
brake. See Electric Parking
Brake 0 241 .
4. Push the key all the way in
toward the steering column,
then turn the key to
LOCK/OFF.
5. Remove the key.
6. Release the brake pedal.
See your dealer if the key can be
removed in any other position.
Retained Accessory Power (RAP)
will remain active. See Retained
Accessory Power (RAP) 0 225 .
A warning chime will sound when
the driver door is opened and the
key is in the ignition.
If equipped with a locking steering
column, the steering can bind with
the front wheels turned off center,
which may prevent key rotation out
of LOCK/OFF. 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. { WarningTurning off the vehicle while
moving may cause loss of power
assist in the brake and steering
systems and disable the airbags.
While driving, turn off the vehicle
only in an emergency.
In an emergency, if the vehicle
cannot be pulled over and must be
turned off while driving:
1. Push the key all the way in
toward the steering column,
then turn the key to ACC/
ACCESSORY.
2. Brake using 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. Continue
braking and steer the vehicle to
a safe location.
4. Come to a complete stop. 5. Shift to P (Park) with an
automatic transmission,
or Neutral with a manual
transmission.
6. Continue to hold the brake
pedal, then set the parking
brake. See Electric Parking
Brake 0 241 .
7. Push the key all the way in
toward the steering column,
then turn the ignition to
LOCK/OFF.
8. Remove the key.
9. Release the brake pedal.
CautionUse the correct key, make sure it
is all the way in — or pushed all
the way in toward the steering
column when turning off the
vehicle — and turn it only with
your hand.
1 (ACC/ACCESSORY) : This
position allows features such as the
infotainment system to operate
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Driving and Operating 219while the vehicle is off. It also
unlocks the steering column,
if equipped with a locking steering
column. Use this position if the
vehicle must be pushed or towed.
See Retained Accessory Power
(RAP) 0 225 .
From ON/RUN, push the key all the
way in toward the steering column,
then turn the key to ACC/
ACCESSORY.
If the key is left in ACC/
ACCESSORY with the engine off,
the battery could drain and the
vehicle may not start.
A warning chime will sound when
the driver door is opened and the
key is in the ignition.
2 (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 ON/RUN with the
engine off, the battery could drain
and the vehicle may not start.
3 (START) : This is the position that
starts the engine. When the engine
starts, release the key. The ignition
returns to ON/RUN for driving.
Ignition Positions
(Keyless Access) Vehicles equipped with Keyless
Access have pushbutton starting.
The Remote Keyless Entry (RKE)
transmitter must be in the vehicle for
the system to operate. If the
pushbutton start is not working, the
vehicle may be near a strong radio
antenna signal causing interference
to the Keyless Access system.
See Remote Keyless Entry (RKE)
System Operation (Keyless Access)
0 33 or Remote Keyless Entry
(RKE) System Operation (Key
Access) 0 41 .
To shift out of P (Park), the ignition
must be on or in Service Mode, 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.
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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220 Driving and Operating 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
ignition will turn off, and Retained
Accessory Power (RAP) will remain
active. See Retained Accessory
Power (RAP) 0 225 .
If the vehicle is not in P (Park), the
ignition will return to ACC/
ACCESSORY and display the
message SHIFT TO PARK in the
Driver Information Center (DIC).
When the vehicle is shifted into
P (Park), the ignition system will
turn off.
The vehicle may have an electric
steering column lock. The lock is
activated when the ignition is turned
off and either front 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.
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.
4. Hold the brake pedal down,
Shift to P (Park) with an
automatic transmission. The
shift lever must be in P (Park)
to turn the ignition off.
5. Continue to hold the brake
pedal down.
6. Set the parking brake, see
Electric Parking Brake 0 241 . 7. Press ENGINE START/STOP
once to turn the ignition off.
8. Release the brake pedal.
If the vehicle cannot be pulled over,
and must be shut off while driving,
press and hold ENGINE START/
STOP for longer than two seconds,
or press twice in five seconds.
ACC/ACCESSORY (Amber
Indicator Light) : This mode allows
some electrical accessories to be
used when the engine is off.
With the ignition off, pressing the
button one time without the brake
pedal applied will place the ignition
system in ACC/ACCESSORY.
The ignition will switch from ACC/
ACCESSORY to off after
five minutes to prevent battery
rundown.
ON/RUN/START (Green Indicator
Light) : This mode is for driving and
starting. With the ignition off, and
the brake pedal applied, pressing
the button once will turn the ignition
on. Once engine cranking begins,
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
Driving and Operating 221release the button. Engine cranking
will continue until the engine starts.
See Starting the Engine 0 221 .
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 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 ignition
is on, but the vehicle will not be able
to be driven. The engine will not
start in Service Mode. Press the
button again to turn the ignition off.
Starting the Engine If the vehicle has a diesel engine,
see the Duramax diesel
supplement. CautionIf 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
0 306 .
Move the shift lever to P (Park) or
N (Neutral). To restart the engine
when the vehicle is already moving,
use N (Neutral) only.
CautionDo 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. For Key Access vehicles, turn
the ignition key to START.
When the engine starts, let go
of the key.
For Keyless Access vehicles,
the RKE transmitter 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 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), hold the ignition switch
in the START position to
continue engine cranking.
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
222 Driving and Operating CautionCranking 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 pushing the
accelerator pedal all the way to
the floor and holding it there
while holding the key in START
or ENGINE START/STOP for
up to a maximum of
15 seconds. Wait at least
15 seconds between each try,
to allow the cranking motor to
cool down. When the engine
starts, let go of the key or button and accelerator. If the
vehicle starts briefly but then
stops again, do the same thing.
This clears the extra gasoline
from the engine. Do not race
the engine immediately after
starting it. Operate the engine
and transmission gently until
the oil warms up and lubricates
all moving parts.
Stop/Start System If equipped, the Stop/Start system
will shut off the engine to help
conserve fuel. It has components
designed for the increased number
of starts.
{ Warning
The automatic engine Stop/Start
feature causes the engine to shut
off while the vehicle is still on. Do
not exit the vehicle before shifting
to P (Park). The vehicle may
restart and move unexpectedly.
(Continued) Warning (Continued) Always shift to P (Park), and then
turn the ignition off before exiting
the vehicle.
Auto Engine Stop/Start
When the brakes are applied and
the vehicle is at a complete stop,
the engine may turn off. When
stopped, the tachometer displays
AUTO STOP. See Tachometer
0 143 . When the brake pedal is
released or the accelerator pedal is
pressed, the engine will restart.
To maintain vehicle performance,
other conditions may cause the
engine to automatically restart
before the brake pedal is released.
Auto Stops may not occur and/or
Auto Starts may occur because:
.
The climate control settings
require the engine to be running
to cool or heat the vehicle
interior.
.
The vehicle battery charge
is low.
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Driving and Operating 223.
The vehicle battery has recently
been disconnected.
.
Minimum vehicle speed has not
been reached since the last
Auto Stop.
.
The accelerator pedal is
pressed.
.
The engine or transmission is
not at the required operating
temperature.
.
The outside temperature is not
in the required operating range.
.
The vehicle is in any gear other
than D (Drive).
.
Tow/Haul Mode or other driver
modes have been selected.
.
The vehicle is on a steep hill or
grade.
.
The driver door has been
opened or the driver seat belt
has been unbuckled.
.
The hood has been opened.
.
The Auto Stop has reached the
maximum allowed time. Auto Stop Disable Switch
If equipped, the automatic engine
Stop/Start feature can be disabled
and enabled by pressing the switch
with the
h symbol. Auto Stop is
enabled each time you start the
vehicle.
When
h is illuminated, the system
is enabled.
Engine Heater The engine heater can provide
easier starting and better fuel
economy during engine warm-up in
cold weather conditions at or below − 18 °C (0 °F). Vehicles with an
engine heater should be plugged in
at least four hours before starting.
An internal thermostat in the
plug-end of the cord may exist,
which will prevent engine heater
operation at temperatures above
− 18 °C (0 °F).
{ WarningDo not plug in the engine block
heater while the vehicle is parked
in a garage or under a carport.
Property damage or personal
injury may result. Always park the
vehicle in a clear open area away
from buildings or structures.
To Use the Engine Heater 1. Turn off the engine.
2. Check the heater cord for
damage. If it is damaged, do
not use it. See your dealer for
a replacement. Inspect the
cord for damage yearly.