GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
48 Keys, Doors, and Windows
Troubleshooting
See your dealer for service if a blue
screen and
3are displayed in
the mirror, and the display shuts off.
Also, push the tab as indicated to
return to the automatic
dimming mode.
The Rear Camera Mirror may not
work properly or display a clear
image if:
. There is glare from the sun or
headlamps. This may obstruct
objects from view. If needed,
push the tab to turn off the
display. .
Dirt, snow, or other debris blocks
the camera lens. Clean the lens
with a soft damp cloth.
. The camera’s mounting on the
vehicle has been damaged, and/
or the position or the mounting
angle of the camera has
changed.
Windows
{Warning
Never leave a child, a helpless
adult, or a pet alone in a vehicle,
especially with the windows
closed in warm or hot weather.
They can be overcome by the
extreme heat and suffer
permanent injuries or even death
from heat stroke.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
166 Lighting
For vehicles first sold in Canada, off
will only work when the vehicle is in
P (Park).
AUTO :Automatically turns on the
headlamps, parking lamps,
taillamps, instrument panel lights,
roof marker lamps (if equipped),
front/rear sidemarker lamps, and
license plate lamps.
;: Turns on the parking lamps
including all lamps, except the
headlamps and fog lamps,
if equipped.
2: Turns on the headlamps
together with the parking lamps,
taillamps, instrument panel lights,
roof marker lamps (if equipped),
front/rear sidemarker lamps, and
license plate lamps.
For some trim levels and series of
trucks first sold in Canada, the
headlamps may turn on with the
parking lamps."
When the headlamps are turned on
while the vehicle is on, the
headlamps turn off automatically
10 minutes after the ignition is
turned off. When the headlamps are turned on while the vehicle is off,
the headlamps will stay on for
10 minutes before turning off to
prevent the battery from being
drained. Turn the headlamp control
off and then back to the headlamp
on position to make the headlamps
stay on for an additional 10 minutes.
To keep the lamps on for more than
10 minutes, the ignition must be on
or in ACC/ACCESSORY.
K:
If equipped, turns on the task
lighting. See Task Lighting 0171.
IntelliBeam System
If equipped, this system turns the
vehicle's high-beam headlamps on
and off according to surrounding
traffic conditions.
The system turns the high-beam
headlamps on when it is dark
enough and there is no other traffic
present.
This light
bcomes on in the
instrument cluster when the
IntelliBeam system is enabled. Turning On and Enabling
IntelliBeam
To enable the IntelliBeam system,
press the button on the end of the
turn signal lever when the exterior
lamp control is in the AUTO or
2
position. The blue high-beam on
light appears on the instrument
cluster when the high beams are on.
Driving with IntelliBeam
The system only activates the high
beams when driving over 40 km/h
(25 mph).
There is a sensor near the top
center of the windshield that
automatically controls the system.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
Driving and Operating 249
When the accelerator pedal is
pressed, ACC will not brake
because it is overridden. The
ACC indicator will turn blue on
the instrument cluster.
. Press and hold RES+ until the
desired set speed is displayed,
then release it.
. To increase vehicle speed in
smaller increments, press RES+
briefly. For each press, the
vehicle goes about 1 km/h (1
mph) faster.
. To increase vehicle speed in
larger increments, hold RES+.
While holding RES+, the vehicle
speed increases to the next
5 km/h (5 mph) step, then
continues to increase by 5 km/h
(5 mph) at a time.
The set speed can also be
increased while the vehicle is
stopped.
. If stopped with the brake pedal
applied, press RES+ until the
desired set speed is displayed. .
Pressing RES+ when there is no
longer a vehicle ahead or the
vehicle ahead is pulling away
and the brake is not applied with
cause the ACC to resume.
When it is determined that there is
no vehicle ahead or the vehicle
ahead is beyond the selected
following gap, then the vehicle
speed will increase to the set speed.
Reducing Speed While ACC Is at a
Set Speed
If ACC is already activated, do one
of the following:
. Use the brake to get to the
desired lower speed. Release
the brake and press SET–. The
vehicle will now cruise at the
lower speed.
. Press and hold SET– until the
desired lower speed is reached,
then release it.
. To decrease the vehicle speed in
smaller increments, press SET−
briefly. For each press, the
vehicle goes about 1 km/h
(1 mph) slower. .
To decrease the vehicle speed in
larger increments, hold SET−.
While holding SET−, the vehicle
speed decreases to the next
5 km/h (5 mph) step, then
continues to decrease by 5 km/h
(5 mph) at a time.
The set speed can also be
decreased while the vehicle is
stopped.
. If stopped with the brake
applied, press or hold SET− until
the desired set speed is
displayed.
Selecting the Follow Distance Gap
When a slower moving vehicle is
detected ahead within the selected
following gap, ACC will adjust the
vehicle's speed and attempt to
maintain the follow distance gap
selected.
Press
[on the steering wheel to
adjust the following gap. Each press
cycles the gap button through three
settings: Far, Medium, or Near.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
252 Driving and Operating
The ACC indicator will turn white
when ACC is no longer active.
In some cases, when ACC is
temporarily unavailable, regular
cruise control may be used. See
“Switching Between ACC and
Regular Cruise Control”previously
in this section. Always consider
driving conditions before using
either cruise control system.
Notification to Resume ACC
ACC will maintain a follow gap
behind a detected vehicle and slow
your vehicle to a stop behind that
vehicle.
If the stopped vehicle ahead has
driven away and ACC has not
resumed, the vehicle ahead
indicator will flash as a reminder to
check traffic ahead before
proceeding. In addition, the left and
right sides of the Safety Alert Seat
will pulse three times, or three
beeps will sound. See ”Alert Type”
and “Adaptive Cruise Go Notifier” in
“Collision/Detection Systems” under
Vehicle Personalization 0157. When the vehicle ahead drives
away, press RES+ or the
accelerator pedal to resume ACC.
If stopped for more than
two minutes or if the driver door is
opened and the driver seat belt is
unbuckled, the ACC automatically
applies the Electric Parking Brake
(EPB) to hold the vehicle. The EPB
status light will turn on. See
Electric
Parking Brake 0233.
A DIC warning message may
display indicating to shift to P (Park)
before exiting the vehicle. See
Vehicle Messages 0156.
{Warning
If ACC has stopped the vehicle,
and if ACC is disengaged, turned
off, or canceled, the vehicle will
no longer be held at a stop. The
vehicle can move. When ACC is
holding the vehicle at a stop,
always be prepared to manually
apply the brakes.
{Warning
Leaving the vehicle without
placing it in P (Park) can be
dangerous. Do not leave the
vehicle while it is being held at a
stop by ACC. Always place the
vehicle in P (Park) and turn off
the ignition before leaving the
vehicle.
ACC Override
If using the accelerator pedal while
ACC is active, the ACC indicator
turns blue on the instrument cluster
indicating ACC braking will not
occur. ACC will resume operation
when the accelerator pedal is not
being pressed.
{Warning
The ACC will not automatically
apply the brakes if your foot is
resting on the accelerator pedal.
You could crash into a vehicle
ahead of you.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
302 Driving and Operating
The seven-wire harness contains
the following trailer circuits:Stop/Turn
Signal Left Yellow/Blue
Stop/Turn
Signal Right Green/Violet
Tail/Parking
Lamps Gray/Brown
Reverse Lamps White/Green
Battery Feed Red/Green
Ground White
Electric Trailer
Brake Blue Heavy-Duty
Trailer Wiring
Harness Package
If equipped, the trailer wiring
harness, with a 7-pin connector and
a
4-pin connector, is mounted on
the vehicle's rear bumper.
The trailer connectors contain the
following circuits.
1. Ground
2. Tail Lamps3. Left Turn/Brake
4. Right Turn/Brake
1. Left Turn/Brake
2. Tail Lamps
3. Reverse Lamps
4. Battery Feed
5. Right Turn/Brake
6. Electric Brakes
7. Ground
If equipped, trailering camera
connectors are available in the
bumper trailer receptacle in place of
the four pin connector. The inside
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
Driving and Operating 303
trailer auxiliary camera should be
installed on the top left hand
side (A) and the rear trailer auxiliary
camera (B) should be installed on
the top right hand side.
If equipped with the fifth wheel/
gooseneck trailer package, the
harness connector is mounted on
the inside of the pickup bed behind
the rear wheel.
Camper/Fifth-Wheel Trailer Wiring
Package
For vehicles without the fifth wheel/
gooseneck trailer 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:
Stop/Turn
Signal Left Yellow/Blue
Stop/Turn
Signal Right Green/Violet
Tail/Parking
Lamps Gray/Brown
Reverse Lamps White/Green
Battery Feed Red/Green
Ground White
Electric Trailer
Brake Blue
If 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.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
Customer Information 475
Cybersecurity
GM collects information about the
use of your vehicle including
operational and safety related
information. We collect this
information to provide, evaluate,
improve, and troubleshoot our
products and services and to
develop new products and services.
The protection of vehicle electronics
systems and customer data from
unauthorized outside electronic
access or control is important to
GM. GM maintains appropriate
security standards, practices,
guidelines and controls aimed at
defending the vehicle and the
vehicle service ecosystem against
unauthorized electronic access,
detecting possible malicious activity
in related networks, and responding
to suspected cybersecurity incidents
in a timely, coordinated and effective
manner. Security incidents could
impact your safety or compromise
your private data. To minimize
security risks, please do not connect
your vehicle electronic systems to
unauthorized devices or connectyour vehicle to any unknown or
untrusted networks (such as
Bluetooth, WIFI or similar
technology). In the event you
suspect any security incident
impacting your data or the safe
operation of your vehicle, please
stop operating your vehicle and
contact your dealer.
Event Data Recorders
This vehicle is equipped with an
event data recorder (EDR). The
main purpose of an EDR is to
record, in certain crash or near
crash-like situations, such as an air
bag deployment or hitting a road
obstacle, data that will assist in
understanding how a vehicle’s
systems performed. The EDR is
designed to record data related to
vehicle dynamics and safety
systems for a short period of time,
typically 30 seconds or less. The
EDR in this vehicle is designed to
record such data as:
.
How various systems in your
vehicle were operating; .
Whether or not the driver and
passenger safety belts were
buckled/fastened;
. How far (if at all) the driver was
depressing the accelerator and/
or brake pedal; and,
. How fast the vehicle was
traveling.
These data can help provide a
better understanding of the
circumstances in which crashes and
injuries occur.
Note
EDR data are recorded by your
vehicle only if a non-trivial crash
situation occurs; no data are
recorded by the EDR under normal
driving conditions and no personal
data (e.g., name, gender, age, and
crash location) are recorded.
However, other parties, such as law
enforcement, could combine the
EDR data with the type of
personally identifying data routinely
acquired during a crash
investigation.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
OnStar 477
OnStar
OnStar Overview
OnStar Overview . . . . . . . . . . . . . 477
OnStar Services
Emergency . . . . . . . . . . . . . . . . . . . 478
Security . . . . . . . . . . . . . . . . . . . . . . 479
OnStar Additional Information
OnStar AdditionalInformation . . . . . . . . . . . . . . . . . . 479
OnStar Overview
=Voice Command Button
QBlue OnStar Button
>Red Emergency Button
This vehicle may be equipped with a
comprehensive, in-vehicle system
that can connect to an OnStar
Advisor for Emergency, Security,
Navigation, Connections, and
Diagnostics Services. OnStar
services may require a paid service
plan and data plan. OnStar requires
the vehicle battery and electrical
system, cellular service, and GPS
satellite signals to be available and
operating. OnStar acts as a link to
existing emergency service
providers. OnStar may collect
information about you and your
vehicle, including location
information. See OnStar User Terms, Privacy Statement, and
Software Terms for more details
including system limitations at
www.onstar.com (U.S.) or
www.onstar.ca (Canada).
The OnStar system status light is
next to the OnStar buttons. If the
status light is:
.
Solid Green: System is ready.
. Flashing Green: On a call.
. Red: Indicates a problem.
. Off: System is off. Press
Q
twice to speak with an OnStar
Advisor.
Press
Qor call 1-888-4ONSTAR
(1-888-466-7827) to speak to an
Advisor.
Functionality of the Voice Command
button may vary by vehicle and
region.