2020 GMC SIERRA DENALI lights

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Driving and Operating 315
Connections OK
If all of the trailer connections are
detected (Running Lights, Left Turn
Signal Light, Right Turn Signal
Light, Reverse Lights, and Electric
Brakes, if equipped), the view will
display OK.
Connection Problem
If any of the trailer connections are
not detected, a message about the
connection issue will appear on the
Driver Information Center (DIC). The
infotainment display will also show
the connection issue in the
Connection Status view.
Diagnose View
Touch Diagnose to see more
information about the connection
problem.
This view will display the names of
the trailer connector pins, a graphic
of the trailer connector, and a
graphic of the back of the trailer.Any connector pin that failed will be
amber color, and the location of the
corresponding connection will be
highlighted on the graphic of the
back of the trailer.
The Running Lights connection may
not detect partial outages. Activate
the light test to check all trailer
lamps. See
“Light Test”following.
If the trailer is not equipped with
reverse lights or electric brakes and
you are receiving failure messages
in the DIC or on this view, turn off
the Reverse Lights Alert or the
Electric Brakes Alert setting in the
trailer ’s profile page.
Light Test
Touch Start Light Test to cycle the
trailer lights on and off to determine
if they are working. The test follows
this sequence: 1. The running lights turn on first and remain on throughout the
sequence.
2. The brake lights turn on for about two seconds. 3. The left turn signal light flashes
three times.
4. The right turn signal light flashes three times.
5. The reverse lights turn on for about two seconds.
6. Steps 2–5 repeat for approximately one minute and
45 seconds, or until the test
deactivates.
Touch Stop to stop the test. The test
will automatically end after
one minute and 45 seconds.
The sequence also deactivates
when any of the following occur:
. The ignition is turned off.
. The transmission is shifted out
of P (Park).
. The brake pedal is pressed.
. The turn signal is activated.
. The hazard warning lights are
activated.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Driving and Operating 319
.Average Fuel Economy
. Reverse Lights Alert
. Electric Brakes Alert
Touch Save to save the new value
to the Trailer Profile. Touching Back
will still save the previously entered
information.
Trailer Name
Touch to edit the Trailer Profile’s
name. Use at least one character
and no spaces. Touch Save.
Towing Assistance Setup
A trailer should be connected to
complete this portion of profile
setup.
Touch to set up the Transparent
Trailer feature for the Trailer Profile.
See "Transparent Trailer Setup"
under "Towing Assistance" for
details on the setup.
Tire Pressure Setup
Touch to set up the Trailer Tire
Pressure Monitoring System
(TTPMS) for the Trailer Profile. See
“Trailer Tire Pressure Setup” previously in this section for details
on the setup. Also, touch Tire
Pressure Setup if the trailer tires
were rotated or if the tire pressure
sensors in the tires were replaced
for this Trailer Profile. The vehicle
will need to relearn the tire sensors
and their locations.
If TTPMS had been set up
previously, the Select Number of
Sensors screen will appear after
touching Tire Pressure Setup. If the
number of sensors has changed,
select the number and touch Next.
If a new number of sensors is
selected, the Relearn Sensors
pop-up will appear. Touch Cancel to
go back or touch Relearn to
overwrite the current sensors and
begin the relearning process. See
“Trailer Tire Pressure Setup”
previously in this section.
If number of sensors has not
changed, touch Next and the Learn
sensors screen will appear.
On the Learn Sensors screen.
Touch Relearn to overwrite the
current sensors and begin therelearning process. See
“Trailer Tire
Pressure Setup” previously in this
section.
On the Learn Sensors screen, touch
Next to go to the Edit
Recommended Tire Pressure
screen.
On the Edit Recommended Tire
Pressure screen, touch a number on
the keypad to change the
Recommended Tire Pressure for the
trailer ’s tires. This will change the
number at which the vehicle
displays alerts related to trailer tire
pressure. Touch Done to return to
the Trailer Profile view.
Trailer Maintenance
Touch to view a list of maintenance
reminders for the Trailer Profile.
Touch a reminder to view, reset,
delete, or edit it.
Reset Reminder
Touch Maintenance Complete in the
reminder view to reset the reminder.
On the pop-up, touch Reset to reset
the time and mileage values for the

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
320 Driving and Operating
reminder. Touch Cancel to return to
the previous view and nothing will
change.
Edit Reminder
Touch to edit the mileage or time
settings for the reminder. Touch
Save to save the new settings to the
Trailer Profile.
Delete Reminder
Touch to delete the maintenance
reminder. On the pop-up, touch
Delete to delete the reminder or
touch Cancel to return to the
previous view and nothing will
change.
New Maintenance Reminder
Touch + New Maintenance
Reminder to set up a new reminder.
Suggested reminders that were
previously set will have checkmarks
next to them. Suggested reminders
that have not been set will have
empty boxes next to them. The
maximum number of reminders
is 50.Mileage
Touch to edit the Trailer Profile’s
mileage.
Effect on Maintenance Reminders
If the mileage is reset or changed,
and mileage has already
accumulated, any maintenance
reminders that have been set up will
be adjusted accordingly.
Average Fuel Economy
Touch to reset the average fuel
economy for the Trailer Profile.
Touch Reset to change, or touch
Cancel to go back to the
previous view.
Reverse Lights Alert
Turn on to receive failure messages
about the reverse lights. Turn off to
not receive failure messages about
the reverse lights, unless they are
later detected. This setting cannot
be edited when the Trailer Profile is
inactive or when the trailer is
disconnected.
Electric Brakes Alert
Turn on to receive failure messages
about the electric trailer brakes.
Turn off to not receive failure
messages about the electric trailer
brakes, unless they are later
detected. This setting cannot be
edited when the Trailer Profile is
inactive or when the trailer is
disconnected.
Delete Trailer
Touch to delete the Trailer Profile
and all of its settings.
On the pop-up, touch Delete to
delete the Trailer Profile. Touch
Cancel to dismiss the pop-up and
return to the previous view.
Settings View
Within the Trailering App, touch the
Settings tab to modify the following
settings:
.
Trailer Detection Alert
. Maintenance Alerts
. Theft Alert
. Tow/Haul Mode Reminder

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
Index 491
Extender, Seat Belt . . . . . . . . . . . . . . 70
Exterior Cargo Lamps . . . . . . . . . . 171
Exterior Lamp Controls . . . . . . . . . 165
Exterior Lamps Off Reminder . . . 167
Exterior Lighting BatterySaver . . . . . . . . . . . . . . . . . . . . . . . . . 174
F
FanEngine . . . . . . . . . . . . . . . . . . . . . . . . 353
Filter, Engine Air Cleaner . . . . . . . . . . . 344
Flash-to-Pass . . . . . . . . . . . . . . . . . . . 168
Flashers, Hazard Warning . . . . . . 169
Flat Tire . . . . . . . . . . . . . . . . . . . . . . . . 405 Changing . . . . . . . . . . . . . . . . . . . . . 407
FlexFuel
E85 . . . . . . . . . . . . . . . . . . . . . . . . . . . 282
Floor Console Storage . . . . . . . . . . 114
Floor Mats . . . . . . . . . . . . . . . . . . . . . . 438
Fluid Automatic Transmission . . . . . . 343
Brakes . . . . . . . . . . . . . . . . . . . . . . . . 357
Four-Wheel DriveTransfer Case . . . . . . . . . . . . . . . 227
Power Steering . . . . . . . . . . . . . . . 354
Washer . . . . . . . . . . . . . . . . . . . . . . . 354
Fog Lamps . . . . . . . . . . . . . . . . . . . . . 170 Folding Mirrors . . . . . . . . . . . . . . . . . . 42
Forward Collision Alert
(FCA) System . . . . . . . . . . . . . . . . . 268
Four-Wheel Drive . . . . . . . . . . 227, 361
Four-Wheel-Drive Light . . . . . . . . . 141
Frequency Statement Radio . . . . . . . . . . . . . . . . . . . . . . . . . 472
Front Axle . . . . . . . . . . . . . . . . . . . . . . 361
Front Fog Lamp Light . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Front Pedestrian Braking
(FPB) System . . . . . . . . . . . . . . . . . 272
Front Seats Adjustment . . . . . . . . . . . . . . . . . . . . . 54
Heated and Ventilated . . . . . . . . . . 60
Fuel
Additives . . . . . . . . . . . . . . . . . . . . . 282
Economy, Driving for Better . . . 186
Filling a Portable FuelContainer . . . . . . . . . . . . . . . . . . . 286
Filling the Tank . . . . . . . . . . 283, 285
Foreign Countries . . . . . . . . . . . . 281
Gauge . . . . . . . . . . . . . . . . . . . . . . . . 131
Low Fuel Warning Light . . . . . . . 145
Management, Active . . . . . . . . . . 219
Prohibited Fuels . . . . . . . . . . . . . . 281
Recommended . . . . . . . . . . 280, 281
Top Tier . . . . . . . . . . . . . . . . . . . . . . 280 Full-Size Spare Tire . . . . . . . . . . . . 418
Fuses
Engine Compartment FuseBlock . . . . . . . . . . . . . . . . . . . . . . . . 371
Fuses and Circuit Breakers . . . 370
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . 374, 376G
Garage Door Opener . . . . . . . . . . . 161
Programming . . . . . . . . . . . . . . . . . 161
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . 365
Gauges
Engine CoolantTemperature . . . . . . . . . . . . . . . . 133
Engine Oil Pressure . . . . . . . . . . 132
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Odometer . . . . . . . . . . . . . . . . . . . . . 131
Speedometer . . . . . . . . . . . . . . . . . 130
Tachometer . . . . . . . . . . . . . . . . . . . 131
Trip Odometer . . . . . . . . . . . . . . . . 131
Voltmeter . . . . . . . . . . . . . . . . . . . . . 134
Warning Lights and Indicators . . . . . . . . . . . . . . . . . . . 125
General Information Service and Maintenance . . . . . 439
Towing . . . . . . . . . . . . . . . . . . . . . . . . 287
Vehicle Care . . . . . . . . . . . . . . . . . . 328

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13337776) - 2020 - CRC - 8/27/19
Index 493
Lamps (cont'd)On Reminder . . . . . . . . . . . . . . . . . 146
Reading . . . . . . . . . . . . . . . . . . . . . . 173
Lane Change Alert (LCA) . . . . . . . 274
Lane Departure
Warning (LDW) . . . . . . . . . . . . . . . . 276
Lane Departure Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Lane Keep Assist (LKA) . . . . . . . . 278
Lane Keep Assist Light . . . . . . . . . 142
Lap-Shoulder Belt . . . . . . . . . . . . . . . 67
LATCH System
Replacing Parts after aCrash . . . . . . . . . . . . . . . . . . . . . . . 104
LATCH, Lower Anchors and Tethers for Children . . . . . . . . . . . . 91
LED Lighting . . . . . . . . . . . . . . . . . . . . 367
Lighting Entry . . . . . . . . . . . . . . . . . . . . . . . . . 173
Exit . . . . . . . . . . . . . . . . . . . . . . . . . . . 173
Illumination Control . . . . . . . . . . . 172
LED . . . . . . . . . . . . . . . . . . . . . . . . . . 367
Task . . . . . . . . . . . . . . . . . . . . . . . . . . 171
Lights Airbag Readiness . . . . . . . . . . . . . 135
Antilock Brake System(ABS) Warning . . . . . . . . . . . . . . 140
Brake System Warning . . . . . . . 139 Lights (cont'd)
Charging System . . . . . . . . . . . . . 137
Check Engine (Malfunction
Indicator) . . . . . . . . . . . . . . . . . . . . 137
Cruise Control . . . . . . . . . . . . . . . . 146
Door Ajar . . . . . . . . . . . . . . . . . . . . . 147
Driver Mode Control . . . . . . . . . . 144
Electric Parking Brake . . . . . . . . 140
Electronic Stability Control (ESC), Off . . . . . . . . . . . . . . . . . . . 143
Engine Coolant Temperature Warning . . . . . . . 144
Engine Oil Pressure . . . . . . . . . . 145
Flash-to-Pass . . . . . . . . . . . . . . . . . 168
Four-Wheel-Drive . . . . . . . . . . . . . 141
Front Fog Lamp . . . . . . . . . . . . . . 146
High-Beam On . . . . . . . . . . . . . . . . 146
High/Low Beam Changer . . . . . 167
Hill Descent Control . . . . . . . . . . 141
Lane Departure Warning . . . . . . 141
Lane Keep Assist . . . . . . . . . . . . . 142
Low Fuel Warning . . . . . . . . . . . . 145
Seat Belt Reminders . . . . . . . . . . 135
Security . . . . . . . . . . . . . . . . . . . . . . 146
Service Electric Parking Brake . . . . . . . . . . . . . . . . . . . . . . . 140
Tire Pressure . . . . . . . . . . . . . . . . . 144
Tow/Haul Mode . . . . . . . . . . . . . . . 141 Lights (cont'd)
Traction Off . . . . . . . . . . . . . . . . . . . 142
Limited-Slip Differential . . . . . . . . . 242
Lock Steering Column . . . . . . . . . . . . . . . . 37
Locking Rear Axle . . . . . . . . . . . . . . 242
Locks Automatic Door . . . . . . . . . . . . . . . . . 27
Delayed Locking . . . . . . . . . . . . . . . . 27
Door . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Lockout Protection . . . . . . . . . . . . . . 28
Power Door . . . . . . . . . . . . . . . . . . . . . 27
Safety . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Loss of Control . . . . . . . . . . . . . . . . . 190
Low Fuel Warning Light . . . . . . . . . 145
Low-Profile Tires . . . . . . . . . . . . . . . . 380
Lower Anchors and Tethers for Children (LATCH
System) . . . . . . . . . . . . . . . . . . . . . . . . 91
Lumbar Adjustment . . . . . . . . . . . . . . 56 Front Seats . . . . . . . . . . . . . . . . . . . . . 56
M
MaintenanceRecords . . . . . . . . . . . . . . . . . . . . . . 456
Maintenance and Care Additional . . . . . . . . . . . . . . . . . . . . . 449
Maintenance Schedule . . . . . . . . . 441

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13337776) - 2020 - CRC - 8/27/19
498 Index
TractionLimited-Slip Differential . . . . . . . 242
Off Light . . . . . . . . . . . . . . . . . . . . . . 142
Traction Control/Electronic Stability Control . . . . . . . . . . . . . . . 235
Trailer Sway Control (TSC) . . . . . . . . . . 308
Tow Mirrors . . . . . . . . . . . . . . . . . . . . . 40
Towing . . . . . . . . . . . . . . . . . . . . . . . . 292
Trailer Towing App . . . . . . . . . . . . . . . . . . . . . . . . . . . 310
Trailering App . . . . . . . . . . . . . . . . . . 310
Transfer Case . . . . . . . . . . . . . . . . . . 227
Transmission Automatic . . . . . . . . . . . . . . . . . . . . . 221
Fluid, Automatic . . . . . . . . . . . . . . 343
Transportation Program, Courtesy . . . . . . . . . . . . . . . . . . . . . . 468
Trip Odometer . . . . . . . . . . . . . . . . . . 131
Truck-Camper Loading Information . . . . . . . . . . . . . . . . . . . . 206
Turn and Lane-Change Signals . . . . . . . . . . . . . . . . . . . . . . . . 170
Turn Signal Bulb Replacement . . . . . . . . . . . . 368U
Underseat Storage . . . . . . . . . . . . . 113
Uniform Tire Quality Grading . . . 402
Universal Remote System . . . . . . 161Operation . . . . . . . . . . . . . . . . . . . . . 164
Programming . . . . . . . . . . . . . . . . . 161
Using This Manual . . . . . . . . . . . . . . . . 2
V
Vehicle Alarm System . . . . . . . . . . . . . . . . . . 36
Canadian Owners . . . . . . . . . . . . . . . 2
Control . . . . . . . . . . . . . . . . . . . . . . . 188
Identification Number (VIN) . . . 457
Load Limits . . . . . . . . . . . . . . . . . . . 200
Messages . . . . . . . . . . . . . . . . . . . . 155
Personalization . . . . . . . . . . . . . . . 156
Remote Start . . . . . . . . . . . . . . . . . . . 25
Security . . . . . . . . . . . . . . . . . . . . . . . . 36
Speed Messages . . . . . . . . . . . . . 156
Towing . . . . . . . . . . . . . . . . . . . . . . . . 424
Vehicle Ahead Indicator . . . . . . . . 142
Vehicle Care Tire Pressure . . . . . . . . . . . . . . . . . 387
Vehicle Data Recording and Privacy . . . . . . . . . . . . . . . . . . . . . . . . 473
Vehicle Security Steering Column Lock . . . . . . . . . . 37 Ventilation, Air . . . . . . . . . . . . . . . . . . 182
Visors . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Voltmeter Gauge . . . . . . . . . . . . . . . 134
W
Warning
Brake System Light . . . . . . . . . . . 139
Caution and Danger . . . . . . . . . . . . . 3
Lane Departure (LDW) . . . . . . . 276
Warning Lights, Gauges, and Indicators . . . . . . . . . . . . . . . . . . . . . 125
Warnings
Hazard Flashers . . . . . . . . . . . . . . 169
Washer Fluid . . . . . . . . . . . . . . . . . . . 354
Wheels Alignment and Tire Balance . . 403
Different Size . . . . . . . . . . . . . . . . . 401
Replacement . . . . . . . . . . . . . . . . . 403
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 399
Where to Put the Restraint . . . . . . 90
Windows . . . . . . . . . . . . . . . . . . . . . . . . 47
Manual . . . . . . . . . . . . . . . . . . . . . . . . . 47
Power . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Windshield
Replacement . . . . . . . . . . . . . . . . . 365
Wiper/Washer . . . . . . . . . . . . . . . . .119