2020 GMC SIERRA DENALI warning light

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Introduction 3
Danger, Warning, and
Caution
Warning messages found on vehicle
labels and in this manual describe
hazards and what to do to avoid or
reduce them.
{Danger
Danger indicates a hazard with a
high level of risk which will result
in serious injury or death.
{Warning
Warning indicates a hazard that
could result in injury or death.
Caution
Caution indicates a hazard that
could result in property or vehicle
damage.
A circle with a slash through it is a
safety symbol which means“Do
not,” “Do not do this,” or“Do not let
this happen.”
Symbols
The vehicle has components and
labels that use symbols instead of
text. Symbols are shown along with
the text describing the operation or
information relating to a specific
component, control, message,
gauge, or indicator.
M: Shown when the owner ’s
manual has additional instructions
or information.
*: Shown when the service
manual has additional instructions
or information.
0: Shown when there is more
information on another page —
“see page.” Vehicle Symbol Chart
Here are some additional symbols
that may be found on the vehicle
and what they mean. See the
features in this manual for
information.
u:
Air Conditioning System
G:Air Conditioning Refrigerant Oil
9:Airbag Readiness Light
!:Antilock Brake System (ABS)
$:Brake System Warning Light
9:Dispose of Used Components
Properly
P: Do Not Apply High Pressure
Water
B: Engine Coolant Temperature
_: Flame/Fire Prohibited
H:Flammable
[:Forward Collision Alert
R: Fuse Block Cover Lock
Location
+: Fuses
j:ISOFIX/LATCH System Child
Restraints

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
6 Introduction
1. Tow/Haul Mode (On SomeModels). See Driver Mode
Control 0238.
Automatic Transfer Case
Control (If Equipped). See
Four-Wheel Drive 0227.
Driver Mode Control 0238 (If
Equipped).
2. Air Vents 0182.
3. Head-Up Display (HUD) 0152
(If Equipped).
4. Turn Signal Lever. See Turn
and Lane-Change Signals
0 170.
Windshield Wiper/Washer
0 119.
5. Instrument Cluster 0126.
6. Shift Lever. See Automatic
Transmission 0221.
Range Selection Mode. See
Manual Mode 0224.
7. Light Sensor. See Automatic
Headlamp System 0168.
8. Infotainment 0176. 9.
Climate Control Systems 0177
(If Equipped).
Dual Automatic Climate Control
System 0179 (If Equipped).
10. Heated and Ventilated Front
Seats 060 (If Equipped).
11.
ALane Keep Assist (LKA)
(1500 Series) 0278 (If
Equipped).
XPark Assist Switch (If
Equipped). See Assistance
Systems for Parking or Backing
0 257.
hAuto Stop Disable Switch
(If Equipped). See Stop/Start
System 0213.
5Power Release Tailgate
(If Equipped). See Tailgate
0 29.
|Hazard Warning Flashers
0 169.
gTraction Control/Electronic
Stability Control 0235.
ADC/AC Switch. See Power
Outlets 0121.
@Lane Departure Warning
(LDW) (2500/3500 Series)
0 276 (If Equipped).
5Hill Descent Control Switch
(If Equipped). See Hill Descent
Control (HDC) 0237.
jPower Assist Steps 034 (If
Equipped).
LExpress Window Down
Button (If Equipped). See
Power Windows 047.
Tow/Haul Mode 0227 (On
Some Models).
12. Power Outlet (Alternating Current) (If Equipped). See
Power Outlets 0121.
13. Power Outlets 0121.
14. USB Port. See the infotainment manual.
15. Wireless Charging 0122 (If
Equipped).

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
10 Keys, Doors, and Windows
{Warning
If the key is unintentionally
rotated while the vehicle is
running, the ignition could be
moved out of the RUN position.
This could be caused by heavy
items hanging from the key ring,
or by large or long items attached
to the key ring that could be
contacted by the driver or
steering wheel. If the ignition
moves out of the RUN position,
the engine will shut off, braking
and steering power assist may be(Continued)
Warning (Continued)
impacted, and airbags may not
deploy. To reduce the risk of
unintentional rotation of the
ignition key, do not change the
way the ignition key and Remote
Keyless Entry (RKE) transmitter,
if equipped, are connected to the
provided key rings.
The ignition key and key rings, and
RKE transmitter, if equipped, are
designed to work together as a
system to reduce the risk of
unintentionally moving the key out
of the RUN position. The ignition
key has a small hole to allow
attachment of the provided key ring.
It is important that any replacement
ignition keys have a small hole. See
your dealer if a replacement key is
required.
The combination and size of the
rings that came with your keys were
specifically selected for your
vehicle. The rings are connected to
the key like two links of a chain to reduce the risk of unintentionally
moving the key out of the RUN
position. Do not add any additional
items to the ring attached to the
ignition key. Attach additional items
only to the second ring, and limit
added items to a few essential keys
or small, light items no larger than
an RKE transmitter.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
48 Keys, Doors, and Windows
Warning (Continued)
prevent operation of the windows.
SeeKeys (Key Access) 09or
Keys (Keyless Access) 012.
The power windows work when the
ignition is on, in ACC/ACCESSORY,
or when Retained Accessory Power
(RAP) is active. See Retained
Accessory Power (RAP) 0216.
Using the window switch, press to
open or pull to close the window. The windows may be temporarily
disabled if they are used repeatedly
within a short time.
Window Lockout
With Power Folding Mirrors,
Without Similar
This feature stops the rear door
passenger window switches from
working except from the driver
position.
Press
2to engage the rear
window lockout feature. The
indicator light is on when engaged.
Press
2again to disengage.
Windows Express Movement
All windows can be opened without
holding the window switch. Press
the switch down fully and quickly
release to express open the
window.
If equipped, pull the window switch
up fully and quickly release to
express close the window.
Briefly press or pull the window
switch in the same direction to stop
that window’s express movement.
Express Window Down
L: If equipped, this button will be
on the center stack.
Press and hold
Lto open all
windows. Release
Lto stop all
movement.
Use the power window switches to
close each window.
Window Automatic Reversal
System
The express-close feature will
reverse window movement if it
comes in contact with an object.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Seats and Restraints 61
Warning (Continued)
overheat. An overheated seat
heater may cause a burn or may
damage the seat.
Heated and Ventilated Seat
Buttons Shown, Heated Seat
Buttons Similar
If equipped, the buttons are on the
center stack. To operate, the engine
must be running.
Press
Ior+to heat the driver or
passenger seatback only. Press
Jorzto heat the driver or
passenger seat cushion and
seatback.
Press
Cor{to ventilate the driver
or passenger seat.
The indicator light on the button
comes on when this feature is on.
Press the button once for the
highest setting. With each press of
the button, the seat will change to
the next lower setting, and then to
the off setting. The indicator lights
next to the buttons indicate three for
the highest setting and one for the
lowest. If the heated seats are on
high for an extended time, their level
may automatically be lowered.
Auto Heated Seats
When the vehicle is on, this feature
will automatically activate the
heated seats at the level required by
the vehicle’ s interior temperature.
The active high, medium, low, or off
heated seat level will be indicated
by the manual heated seat buttons
on the center stack. Use the manual
heated seat buttons on the center stack to turn auto heated seats off.
If the passenger seat is unoccupied,
the auto heated seats feature will
not activate that seat. The auto
heated seats feature can be
programmed to always be enabled
when the vehicle is on. See
Vehicle
Personalization 0156.
Remote Start Heated and
Ventilated Seats
If equipped, the heated seats will
turn on automatically during a
remote start if it is cold outside and
the ventilated seats will turn on
automatically if it is hot outside.
If equipped, the heated steering
wheel will turn on automatically
during a remote start if it is cold
outside. The heated and ventilated
seat indicators and heated steering
wheel indicator may not come on
during this operation.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
64 Seats and Restraints
This feature turns on at the highest
setting. With each press of the
button, the heated seat changes to
the next lower setting, and then the
off setting. Three lights indicate the
highest setting, and one light
indicates the lowest. If the heated
seats are on high, the level may
automatically be lowered after
approximately 30 minutes.Seat Belts
This section describes how to use
seat belts properly, and some things
not to do.
{Warning
Do not let anyone ride where a
seat belt cannot be worn properly.
In a crash, if you or your
passenger(s) are not wearing
seat belts, injuries can be much
worse than if you are wearing
seat belts. You can be seriously
injured or killed by hitting things
inside the vehicle harder or by
being ejected from the vehicle. In
addition, anyone who is not
buckled up can strike other
passengers in the vehicle.
It is extremely dangerous to ride
in a cargo area, inside or outside
of a vehicle. In a collision,
passengers riding in these areas
are more likely to be seriously
injured or killed. Do not allow(Continued)
Warning (Continued)
passengers to ride in any area of
the vehicle that is not equipped
with seats and seat belts.
Always wear a seat belt, and
check that all passenger(s) are
restrained properly too.
This vehicle has indicators as a
reminder to buckle the seat belts.
See Seat Belt Reminders 0135.
Why Seat Belts Work

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Seats and Restraints 67
Always use the correct buckle for
your seating position.
Never route the lap or shoulder belt
over an armrest.
{Warning
The seat belt can be pinched if it
is routed under plastic trim on the
seat, such as trim around the rear
seatback folding handle or side
airbag. In a crash, pinched seat
belts might not be able to provide
adequate protection. Never allow
seat belts to be routed under
plastic trim pieces.
Lap-Shoulder Belt
All seating positions in the vehicle
have a lap-shoulder belt.
The following instructions explain
how to wear a lap-shoulder belt
properly.1. Adjust the seat, if the seat is adjustable, so you can sit up
straight. To see how, see
“Seats” in the Index.
2. Pick up the latch plate and pull
the belt across you. Do not let
it get twisted.
The lap-shoulder belt may lock
if you pull the belt across you
very quickly. If this happens, let
the belt go back slightly to
unlock it. Then pull the belt
across you more slowly.
If the shoulder portion of a
passenger belt is pulled out all
the way, the child restraint
locking feature may be
engaged. See Child Restraint
Systems 088. If this occurs, let
the belt go back all the way
and start again. If the locking

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Seats and Restraints 71
{Warning
Do not bleach or dye seat belt
webbing. It may severely weaken
the webbing. In a crash, they
might not be able to provide
adequate protection. Clean and
rinse seat belt webbing only with
mild soap and lukewarm water.
Allow the webbing to dry.
Replacing Seat Belt
System Parts after a
Crash
{Warning
A crash can damage the seat belt
system in the vehicle. A damaged
seat belt system may not properly
protect the person using it,
resulting in serious injury or even
death in a crash. To help make
sure the seat belt systems are
working properly after a crash,(Continued)
Warning (Continued)
have them inspected and any
necessary replacements made as
soon as possible.
After a minor crash, replacement of
seat belts may not be necessary.
But the seat belt assemblies that
were used during any crash may
have been stressed or damaged.
See your dealer to have the seat
belt assemblies inspected or
replaced.
New parts and repairs may be
necessary even if the seat belt
system was not being used at the
time of the crash.
Have the seat belt pretensioners
checked if the vehicle has been in a
crash, or if the airbag readiness light
stays on after you start the vehicle
or while you are driving. See Airbag
Readiness Light 0135.
Airbag System
The vehicle has the following
airbags:
.
A frontal airbag for the driver
. A frontal airbag for the front
outboard passenger
. A seat-mounted side impact
airbag for the driver
. A seat-mounted side impact
airbag for the front outboard
passenger
. A roof-rail airbag for the driver
and the passenger seated
directly behind the driver
. A roof-rail airbag for the front
outboard passenger and the
passenger seated directly
behind the front outboard
passenger
All vehicle airbags have the word
AIRBAG on the trim or on a label
near the deployment opening.