2020 GMC SIERRA DENALI stop start

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
392 Vehicle Care
the sensor matching process is
performed successfully. See
your dealer for service.
. Replacement tires or wheels do
not match the original equipment
tires or wheels. Tires and wheels
other than those recommended
could prevent the TPMS from
functioning properly. See Buying
New Tires 0399.
. Operating electronic devices or
being near facilities using radio
wave frequencies similar to the
TPMS could cause the TPMS
sensors to malfunction.
If the TPMS is not functioning
properly, it cannot detect or signal a
low tire pressure condition. See
your dealer for service if the TPMS
malfunction light and DIC message
come on and stay on.
Tire Fill Alert (If Equipped)
This feature provides visual and
audible alerts outside the vehicle to
help when inflating an underinflated
tire to the recommended cold tire
pressure. When the low tire pressure warning
light comes on:
1. Park the vehicle in a safe, level place.
2. Set the parking brake firmly.
3. Place the vehicle in P (Park).
4. Add air to the tire that is underinflated. The turn signal
lamp will flash.
When the recommended
pressure is reached, the horn
sounds once and the turn
signal lamp will stop flashing
and briefly turn solid.
Repeat these steps for all
underinflated tires that have
illuminated the low tire pressure
warning light.
{Warning
Overinflating a tire could cause
the tire to rupture and you or
others could be injured. Do not
exceed the maximum pressure (Continued)
Warning (Continued)
listed on the tire sidewall. See
Tire Sidewall Labeling 0381 and
Vehicle Load Limits 0200.
If the tire is overinflated by more
than 35 kPa (5 psi), the horn will
sound multiple times and the turn
signal lamp will continue to flash for
several seconds after filling stops.
To release and correct the pressure,
while the turn signal lamp is still
flashing, briefly press the center of
the valve stem. When the
recommended pressure is reached,
the horn sounds once.
If the turn signal lamp does not flash
within 15 seconds after starting to
inflate the tire, the tire fill alert has
not been activated or is not working.
If the hazard warning flashers are
on, the tire fill alert visual feedback
will not work properly.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Vehicle Care 393
The TPMS will not activate the tire
fill alert properly under the following
conditions:
.There is interference from an
external device or transmitter.
. The air pressure from the
inflation device is not sufficient
to inflate the tire.
. There is a malfunction in
the TPMS.
. There is a malfunction in the
horn or turn signal lamps.
. The identification code of the
TPMS sensor is not registered to
the system.
. The battery of the TPMS sensor
is low.
If the tire fill alert does not operate
due to TPMS interference, move the
vehicle about 1 m (3 ft) back or
forward and try again. If the tire fill
alert feature is not working, use a
tire pressure gauge.TPMS Sensor Matching
Process
Each TPMS sensor has a unique
identification code. The identification
code needs to be matched to a new
tire/wheel position after rotating the
vehicle’s tires or replacing one or
more of the TPMS sensors. Also,
the TPMS sensor matching process
should be performed after replacing
a spare tire with a road tire
containing the TPMS sensor. The
malfunction light and the DIC
message should go off at the next
ignition cycle. The sensors are
matched to the tire/wheel positions,
using a TPMS relearn tool, in the
following order: driver side front tire,
passenger side front tire, passenger
side rear tire, and driver side rear.
See your dealer for service or to
purchase a relearn tool. A TPMS
relearn tool can also be purchased.
See Tire Pressure Monitor Sensor
Activation Tool at
www.gmtoolsandequipment.com or
call 1-800-GM TOOLS
(1-800-468-6657). There are two minutes to match the
first tire/wheel position, and
five minutes overall to match all four
tire/wheel positions. If it takes
longer, the matching process stops
and must be restarted.
The TPMS sensor matching
process is:
1. Set the parking brake.
2. Turn the ignition on without starting the vehicle.
3. Uplevel DIC Only: Make sure the Tire Pressure info page
option is turned on. The info
pages on the DIC can be
turned on and off through the
Options menu. See Driver
Information Center (DIC) (Base
Level) 0147 or
Driver Information Center (DIC)
(Midlevel and Uplevel) 0148.
4. If the vehicle has an uplevel DIC, use the DIC controls on
the right side of the steering
wheel to scroll to the Tire
Pressure screen under the DIC
info page.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Vehicle Care 419
should not be driven on over
112 km/h (70 mph), or 88 km/h
(55 mph) when pulling a trailer, at
the proper inflation pressure. Repair
and replace the road tire as soon as
it is convenient, and stow the spare
tire for future use.
Caution
If the vehicle has four-wheel drive
and a different size spare tire is
installed, do not drive in
four-wheel drive until the flat tire
is repaired and/or replaced. The
vehicle could be damaged and
the repairs would not be covered
by the warranty. Never use
four-wheel drive when a different
size spare tire is installed on the
vehicle.
The vehicle may have a different
size spare tire than the road tires
originally installed on the vehicle. This spare tire was developed for
use on this vehicle, so it is all right
to drive on it. If the vehicle has
four-wheel drive and a different size
spare tire is installed, drive only in
two-wheel drive.
After installing the spare tire on the
vehicle, stop as soon as possible
and check that the spare tire is
correctly inflated.
Have the damaged or flat road tire
repaired or replaced and installed
back onto the vehicle as soon as
possible so the spare tire will be
available in case it is needed again.
Do not mix tires and wheels of
different sizes, because they will not
fit. Keep your spare tire and its
wheel together. If the vehicle has a
spare tire that does not match the
original road tires and wheels in size
and type, do not include the spare in
the tire rotation.
Jump Starting
Jump Starting - North
America
For more information about the
vehicle battery, see
Battery - North
America 0358.
If the vehicle's battery (or batteries)
has run down, you may want to use
another vehicle and some jumper
cables to start your vehicle. Be sure
to use the following steps to do it
safely.
{Warning
WARNING: Battery posts,
terminals, and related
accessories contain lead and lead
compounds, chemicals known to
the State of California to cause
cancer and birth defects or other
reproductive harm. Batteries also
contain other chemicals known to
the State of California to cause
cancer. WASH HANDS AFTER
(Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Vehicle Care 427
Warning (Continued)
negative battery cable and cover
the negative battery post and
cable with a non-conductive
material. If the battery is left
connected or the battery cable
contacts the post, the Electric
Parking Brake may activate
during towing, which could cause
a crash.
8. Disconnect the negative (–) battery cable. See “Negative
Battery Cable Disconnection”
in Battery - North America
0 358.
9. Shift the transmission to P (Park).
Caution
If the steering column is locked,
vehicle damage may occur. 10. Move the steering wheel to
make sure the steering column
is unlocked.
11. If the vehicle has an ignition key, keep it in the towed
vehicle in ACC/ACCESSORY
to prevent the steering column
from locking. If the vehicle is
equipped with Keyless Access,
keep the RKE transmitter
outside of the vehicle and
manually lock the doors.
Access the vehicle by using
the key in the door lock. See
Door Locks 026.
Disconnecting the Towed Vehicle
Before disconnecting from the tow
vehicle: 1. Park on a level surface. Secure the vehicle with wheel blocks.
2. Re-connect the negative (–) battery. See Battery - North
America 0358. 3. Turn on the ignition with the
engine off. For vehicles with a
key, turn the ignition to ON/
RUN with the engine off. If the
vehicle is equipped with
Keyless Access, with your foot
off the brake pedal, press and
hold ENGINE START/STOP for
five seconds until the green
light comes on in the button.
See Ignition Positions (Keyless
Access) 0208 or
Ignition Positions (Key Access)
0 210.
4. Set the parking brake. See Electric Parking Brake 0233.
5. Disconnect from the tow vehicle.
6. Shift the transmission to N (Neutral).
7. Shift the transfer case to 2
m
(Two-Wheel Drive High). When
the shift to 2
m(Two-Wheel
Drive High) is complete, the
light in the instrument cluster
will stop flashing and stay lit.
See Four-Wheel-Drive Light
0 141.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Service and Maintenance 449
Additional
Maintenance and Care
Your vehicle is an important
investment and caring for it properly
may help to avoid future costly
repairs. To maintain vehicle
performance, additional
maintenance services may be
required.
It is recommended that your dealer
perform these services—their
trained dealer technicians know
your vehicle best. Your dealer can
also perform a thorough
assessment with a multi-point
inspection to recommend when your
vehicle may need attention.
The following list is intended to
explain the services and conditions
to look for that may indicate
services are required.
Battery
The 12-volt battery supplies power
to start the engine and operate any
additional electrical accessories. .
To avoid break-down or failure to
start the vehicle, maintain a
battery with full cranking power.
. Trained dealer technicians have
the diagnostic equipment to test
the battery and ensure that the
connections and cables are
corrosion-free.
Belts
. Belts may need replacing if they
squeak or show signs of
cracking or splitting.
. Trained dealer technicians have
access to tools and equipment
to inspect the belts and
recommend adjustment or
replacement when necessary.
Brakes
Brakes stop the vehicle and are
crucial to safe driving.
. Signs of brake wear may include
chirping, grinding, or squealing
noises, or difficulty stopping. .
Trained dealer technicians have
access to tools and equipment
to inspect the brakes and
recommend quality parts
engineered for the vehicle.
Fluids
Proper fluid levels and approved
fluids protect the vehicle’s systems
and components. See
Recommended Fluids and
Lubricants 0452 for GM approved
fluids.
. Engine oil and windshield
washer fluid levels should be
checked at every fuel fill.
. Instrument cluster lights may
come on to indicate that fluids
may be low and need to be
filled.
Hoses
Hoses transport fluids and should
be regularly inspected to ensure
that there are no cracks or leaks.
With a multi-point inspection, your
dealer can inspect the hoses and
advise if replacement is needed.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
486 Connected Services
vehicles, the SSID and
password can be changed in
the Wi-Fi Hotspot menu.
After initial set-up, your vehicle’s
Wi-Fi hotspot will connect
automatically to your mobile
devices. Manage data usage by
turning Wi-Fi on or off on your
mobile device, using the myGMC
mobile app, or by contacting an
OnStar Advisor. On some vehicles,
Wi-Fi can also be managed from the
Wi-Fi Hotspot menu.
MyGMC Mobile App (If Available)
Download the myGMC mobile app
to compatible Apple and Android
smartphones. GMC users can
access the following services from a
smartphone:
. Remotely start/stop the vehicle,
if factory-equipped.
. Lock/unlock doors, if equipped
with automatic locks.
. Activate the horn and lamps. .
Check the vehicle’s fuel level, oil
life, or tire pressure,
if factory-equipped with the Tire
Pressure Monitor System.
. Send destinations to the vehicle.
. Locate the vehicle on a map
(U.S. market only).
. Turn the vehicle's Wi-Fi hotspot
on/off, manage settings, and
monitor data consumption,
if equipped.
. Locate a dealer and schedule
service.
. Request roadside assistance.
. Set a parking reminder with pin
drop, take a photo, make a note,
and set a timer.
. Connect with GMC on social
media.
Features are subject to change. For
myGMC mobile app information and
compatibility, see my.gmc.com.
An active OnStar or connected
service plan may be required.
A compatible device,
factory-installed remote start, and power locks are required. Data rates
apply. See www.onstar.com for
details and system limitations.
Remote Services
Contact an OnStar Advisor to
unlock the doors or sound the horn
and flash the lamps.
Marketplace
OnStar Advisors can provide offers
from restaurants and retailers on
your route, help locate hotels,
or book a room. These services
vary by market.
Diagnostics
By monitoring and reporting on the
vehicle's key systems, OnStar
Advanced Diagnostics, if equipped,
provides a way to keep up on
maintenance. Capabilities vary by
model. See www.onstar.com for
details and system limitations.
Features are subject to change. For
updates on feature capabilities, see
my.gmc.com. Message and data
rates may apply.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13337776) - 2020 - CRC - 8/27/19
488 Index
Assistance Program,Roadside . . . . . . . . . . . . . . . . . . . . . . 466
Assistance Systems for Driving . . . . . . . . . . . . . . . . . . . . . . . . 268
Assistance Systems for Parking and Backing . . . . . . . . . . 257
Auto Stop
Stop/Start System . . . . . . . . . . . . 213
Automatic Dimming Mirrors . . . . . . . . . . . . . . . . 43
Door Locks . . . . . . . . . . . . . . . . . . . . . 27
Emergency Braking (AEB) . . . . 270
Headlamp System . . . . . . . . . . . . 168
Transmission . . . . . . . . . . . . . . . . . 221
Transmission Fluid . . . . . . . . . . . 343
Automatic Transmission
Manual Mode . . . . . . . . . . . . . . . . . 224
Shift Lock Control FunctionCheck . . . . . . . . . . . . . . . . . . . . . . . 363
Axle, Front . . . . . . . . . . . . . . . . . . . . . . 361
Axle, Rear . . . . . . . . . . . . . . . . . . . . . . 362
B
Battery Exterior Lighting BatterySaver . . . . . . . . . . . . . . . . . . . . . . . 174
Load Management . . . . . . . . . . . . 174 Battery (cont'd)
Power Protection . . . . . . . . . . . . . 174
Battery - North America . . . . 358, 419
Blade Replacement, Wiper . . . . . 364
Blind Spot Mirrors . . . . . . . . . . . . . . . 43
Brake Electric Boost . . . . . . . . . . . . . . . . . 232
Parking, Electric . . . . . . . . . . . . . . 233
System Warning Light . . . . . . . . 139
Brake Pad Life System . . . . . . . . . 356
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . 355 Antilock . . . . . . . . . . . . . . . . . . . . . . . 232
Assist . . . . . . . . . . . . . . . . . . . . . . . . . 234
Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 357
Pad Life System . . . . . . . . . . . . . . 356
Braking . . . . . . . . . . . . . . . . . . . . . . . . . 188 AutomaticEmergency (AEB) . . . . . . . . . . . 270
Braking System Front Pedestrian (FPB) . . . . . . . 272
Break-In, New Vehicle . . . . . . . . . . 208
Bulb Replacement Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . . . 369
Halogen Bulbs . . . . . . . . . . . . . . . . 367
Headlamp Aiming . . . . . . . . . . . . . 366
Headlamps . . . . . . . . . . . . . . . . . . . 367 Bulb Replacement (cont'd)
Headlamps, Front Turn
Signal, Sidemarker, and
Parking Lamps . . . . . . . . . . . . . . 367
License Plate Lamps . . . . . . . . . 369
Taillamps, Turn Signal, Stoplamps, and Back-up
Lamps . . . . . . . . . . . . . . . . . . . . . . 368
Buying New Tires . . . . . . . . . . . . . . . 399
C
Calibration . . . . . . . . . . . . . . . . . . . . . . 120
California Perchlorate Materials
Requirements . . . . . . . . . . . . . . . 329
California Proposition
65 Warning . . . . . . . . . .329, 358, 419, Back Cover
Canadian Vehicle Owners . . . . . . . . 2
Capacities and Specifications . . . . . . . . . . . . . . . . . 458
Carbon Monoxide Engine Exhaust . . . . . . . . . . . . . . . 220
Tailgate . . . . . . . . . . . . . . . . . . . . . . . . . 29
Winter Driving . . . . . . . . . . . . . . . . 197
Cargo Tie-Downs . . . . . . . . . . . . . . . . . . . . .115

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13337776) - 2020 - CRC - 8/27/19
Index 497
Steering (cont'd)Wheel Adjustment . . . . . . . . . . . . .118
Wheel Controls . . . . . . . . . . . . . . . .119
Steering Column Lock . . . . . . . . . . . 37
Steps
Power Assist . . . . . . . . . . . . . . . . . . . 34
Stop/Start System . . . . . . . . . . . . . . 213
Stoplamps and Back-up Lamps Bulb Replacement . . . . . . . . . . . . 368
Storage Rear . . . . . . . . . . . . . . . . . . . . . . . . . . .113
Storage Areas Center Console . . . . . . . . . . . . . . . .113
Floor Console . . . . . . . . . . . . . . . . .114
Glove Box . . . . . . . . . . . . . . . . . . . . .112
Underseat . . . . . . . . . . . . . . . . . . . . .113
Storage Compartments . . . . . . . . . 112
Struts Gas . . . . . . . . . . . . . . . . . . . . . . . . . . . 365
Stuck Vehicle . . . . . . . . . . . . . . . . . . . 199
Sun Visors . . . . . . . . . . . . . . . . . . . . . . . 50
Sunroof . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . 3
System Brake Pad Life . . . . . . . . . . . . . . . . 356
Engine Air Filter Life . . . . . . . . . . 343
Forward CollisionAlert (FCA) . . . . . . . . . . . . . . . . . . 268 System (cont'd)
Infotainment . . . . . . . . . . . . . 176, 475
Noise Control . . . . . . . . . . . . . . . . . 362
Systems
Driver Assistance . . . . . . . . . . . . . 255
T
Tachometer . . . . . . . . . . . . . . . . . . . . . 131
Tailgate . . . . . . . . . . . . . . . . . . . . . . . . . . 29
TaillampsBulb Replacement . . . . . . . . . . . . 368
Task Lighting . . . . . . . . . . . . . . . . . . . 171
Text Telephone (TTY) Users . . . . 465
Theft-Deterrent Systems . . . . . . . . . 37 Immobilizer . . . . . . . . . . . . . . . . . . . . . 37
Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . 379 All-Season . . . . . . . . . . . . . . . . . . . . 379
All-Terrain . . . . . . . . . . . . . . . . . . . . 381
Buying New Tires . . . . . . . . . . . . . 399
Chains . . . . . . . . . . . . . . . . . . . . . . . . 404
Changing . . . . . . . . . . . . . . . . . . . . . 407
Designations . . . . . . . . . . . . . . . . . 383
Different Size . . . . . . . . . . . . . . . . . 401
Full-Size Spare . . . . . . . . . . . . . . . 418
If a Tire Goes Flat . . . . . . . . . . . . 405
Inspection . . . . . . . . . . . . . . . . . . . . 396
Low Profile . . . . . . . . . . . . . . . . . . . 380 Tires (cont'd)
Pressure . . . . . . . . . . . . . . . . . 387, 389
Pressure Light . . . . . . . . . . . . . . . . 144
Pressure Monitor Operation . . 390
Pressure Monitor System . . . . . 389
Rotation . . . . . . . . . . . . . . . . . . . . . . 396
Sidewall Labeling . . . . . . . . . . . . . 381
Terminology and Definitions . . 385
Uniform Tire Quality
Grading . . . . . . . . . . . . . . . . . . . . . 402
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . 403
Wheel Replacement . . . . . . . . . . 403
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . 399
Winter . . . . . . . . . . . . . . . . . . . . . . . . 380
Top Tier Fuel . . . . . . . . . . . . . . . . . . . 280
Tow/Haul Mode . . . . . . . . . . . . . . . . . 227
Tow/Haul Mode Light . . . . . . . . . . . 141
Towing Driving Characteristics . . . . . . . . 287
Equipment . . . . . . . . . . . . . . . . . . . . 296
General Information . . . . . . . . . . 287
Recreational Vehicle . . . . . . . . . . 424
Trailer . . . . . . . . . . . . . . . . . . . . . . . . 292
Trailer Sway Control (TSC) . . . 308
Vehicle . . . . . . . . . . . . . . . . . . . . . . . 424