warning lights GMC YUKON 2021 User Guide

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Driving and Operating 297
Warning (Continued)
carefully pull the vehicle over to the
side of the road when traffic
conditions allow.
Trailer Tires
Special Trailer (ST) tires differ from vehicle
tires. Trailer tires are designed with stiff
sidewalls to help prevent sway and to
support heavy loads. These features can
make it difficult to determine if the trailer
tire pressures are low only based on a visual
inspection.
Always check all trailer tire pressures before
each trip when the tires are cool. Low trailer
tire pressure is a leading cause of trailer tire
blow-outs.
If the vehicle is equipped with a trailer tire
pressure monitoring system, see the trailer
tire pressure monitoring system description
and the trailering app.
Trailer tires deteriorate over time. The trailer
tire sidewall will show the week and year
the tire was manufactured. Many trailer tire
manufacturers recommend replacing tires
more than six years old.Overloading is another leading cause of
trailer tire blow-outs. Never load your trailer
with more weight than the tires are
designed to support. The load rating is
located on the trailer tire sidewall.
Always know the maximum speed rating for
the trailer tires before driving. This may be
significantly lower than the vehicle tire
speed rating. The speed rating may be on
the trailer tire sidewall. If the speed rating is
not shown, the default trailer tire speed
rating is 105 km/h (65 mph).
Trailering App
Trailer Lights App
If equipped, the Trailer Lights App is on the
Home Page of the infotainment display.
Touch Start to cycle the trailer lamps 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.
Trailering App
If equipped, the Trailering App is on the
Home Page of the infotainment display.
If equipped this feature allows profiles for
connected trailers to be created to view
status, to store and track trailer usage
information, and to set up towing assistance
features.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Driving and Operating 301
Connection Trailer Lighting Faults Detected
The Trailering App System monitors for
electrical faults on the trailer lights.
A message about the lighting issue will
appear on the DIC. The infotainment display
will also show the lighting issue in the
Connection Status view. Repair your trailer
lights if needed. A trailer lighting issue is
not covered by your GM warranty.
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. 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.
Tires
1. Trailer Tire Pressure/Temperature
Tire Pressure and Temperature
If the TTPMS sensor-to-vehicle learn process
was completed, the status view will display
the current tire pressure and temperature of
the trailer tires related to the active Trailer
Profile. If a tire’s pressure is low or high, the
color of the pressure value will be amber.
If a sensor malfunctions, the values are
dashed lines. If the screen displays “Service
Tire Pressure Monitoring System”, the
vehicle needs to be taken to a dealer for
service.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./Cana-
da/Mexico-13690468) - 2021 - crc - 8/14/20
422 Index
Front Fog LampLight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Front Pedestrian Braking (FPB) System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270
Front Seats Heated and Ventilated . . . . . . . . . . . . . . . . . . 44
Fuel
Additives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
Dynamic Management . . . . . . . . . . . . . . . . . 231
Economy, Driving for Better . . . . . . . . . . . 213
Filling a Portable Fuel Container . . . . . . . 279
Filling the Tank . . . . . . . . . . . . . . . . . . . . . . . . 278
Foreign Countries . . . . . . . . . . . . . . . . . . . . . . 278
Gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Low Fuel Warning Light . . . . . . . . . . . . . . . . 118
Prohibited Fuels . . . . . . . . . . . . . . . . . . . . . . . 277
Recommended . . . . . . . . . . . . . . . . . . . . . . . . . 277
Top Tier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276
Full-Size Spare Tire . . . . . . . . . . . . . . . . . . . . . . . 366
Fuses Engine Compartment Fuse Block . . . . . . . 332
Fuses and Circuit Breakers . . . . . . . . . . . . . 331
Instrument Panel Fuse Block . . . . . . . . . . . 335
Rear Compartment Fuse Block . . . . . . . . . 337
G
Garage Door Opener . . . . . . . . . . . . . . . . . . . . . . 131 Garage Door Opener (cont'd)
Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330
Gauges Engine Coolant Temperature . . . . . . . . . . . 108
Engine Oil Pressure . . . . . . . . . . . . . . . . . . . . 107
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Odometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Speedometer . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Tachometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Trip Odometer . . . . . . . . . . . . . . . . . . . . . . . . . 106
Voltmeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Warning Lights and Indicators . . . . . . . . . 103
General Information Service and Maintenance . . . . . . . . . . . . . . 383
Towing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 280
Vehicle Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 309
Glass Replacement . . . . . . . . . . . . . . . . . . . . . . . 330
Global Positioning System (GPS) . . . . . . . . . .174
Glove Box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
GM Mobility Reimbursement Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 402
Guidance Problems with the Route . . . . . . . . . . . . . . . 175
H
Hazard Warning Flashers . . . . . . . . . . . . . . . . . 137
HD Radio Technology . . . . . . . . . . . . . . . . . . . . 149
Head Restraints . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
Head-up Display . . . . . . . . . . . . . . . . . . . . . . . . . . 122
HeadlampsAiming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
Automatic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Daytime Running Lamps (DRL) . . . . . . . . . 136
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
High-Beam On Light . . . . . . . . . . . . . . . . . . . . 119
High/Low Beam Changer . . . . . . . . . . . . . . 136
Lamps On Reminder . . . . . . . . . . . . . . . . . . . . 119
Heated
Rear Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Steering Wheel . . . . . . . . . . . . . . . . . . . . . . . . . 96
Heated and Ventilated Front Seats . . . . . . . 44
Heated Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204, 207
High-Beam On Light . . . . . . . . . . . . . . . . . . . . . . 119
High-Speed Operation . . . . . . . . . . . . . . . . . . . 345
Hill and Mountain Roads . . . . . . . . . . . . . . . . 220
Hill Descent Control (HDC) . . . . . . . . . . . . . . . 244
Hill Descent Control Light . . . . . . . . . . . . . . . . . 114
Hill Start Assist (HSA) . . . . . . . . . . . . . . . . . . . . 242
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 310
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
How to Wear Seat Belts Properly . . . . . . . . . 54

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./Cana-
da/Mexico-13690468) - 2021 - crc - 8/14/20
Index 423
HVAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204, 207
I
If the System Needs Service . . . . . . . . . . . . . . 175
Ignition Positions . . . . . . . . . . . . . . . . . . . . . . . . 226
Immobilizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
IndicatorPedestrian Ahead . . . . . . . . . . . . . . . . . . . . . . . 115
Vehicle Ahead . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Infants and Young Children, Restraints . . . . .72
Information Publication Ordering . . . . . . . . . . . . . . . . . . . 406
Infotainment System . . . . . . . . . . . . . . . . . . . . 409 Rear Seat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156
Instrument Cluster . . . . . . . . . . . . . . . . . . . . . . . 104
Instrument Panel Storage Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Instrument Panel Overview . . . . . . . . . . . . . . . . 4
Interior Rearview Mirrors . . . . . . . . . . . . . . . . . 30
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 1, 142
J
Jump Starting - North America . . . . . . . . . . . 367
K
Keyless Entry Remote (RKE) System . . . . . . . . . . . . . . . . . . . . 8
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
L
Labeling, Tire Sidewall . . . . . . . . . . . . . . . . . . . .341
Lamps
Daytime Running (DRL) . . . . . . . . . . . . . . . . 136
Dome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
Exterior Controls . . . . . . . . . . . . . . . . . . . . . . . 134
Exterior Lamps Off Reminder . . . . . . . . . . 136
Exterior Lighting Battery Saver . . . . . . . . . 141
Malfunction Indicator (CheckEngine) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
On Reminder . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
Lane Change Alert (LCA) . . . . . . . . . . . . . . . . . 272
Lane Keep Assist (LKA) . . . . . . . . . . . . . . . . . . . 275
Lane Keep Assist Light . . . . . . . . . . . . . . . . . . . . 114
Lap-Shoulder Belt . . . . . . . . . . . . . . . . . . . . . . . . . 56
LATCH System Replacing Parts after a Crash . . . . . . . . . . . 83
LATCH, Lower Anchors and Tethers for
Children . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77
LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
Liftgate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Lighting Entry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Exit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Illumination Control . . . . . . . . . . . . . . . . . . . 139
LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331 Lights
Airbag Readiness . . . . . . . . . . . . . . . . . . . . . . 109
Antilock Brake System (ABS)
Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Brake System Warning . . . . . . . . . . . . . . . . . 112
Charging System . . . . . . . . . . . . . . . . . . . . . . . 111
Check Engine (Malfunction Indicator) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Cruise Control . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Door Ajar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Driver Mode Control . . . . . . . . . . . . . . . . . . . . 116
Electric Parking Brake . . . . . . . . . . . . . . . . . . . 113
Electronic Stability Control (ESC), Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Engine Coolant Temperature Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Engine Oil Pressure . . . . . . . . . . . . . . . . . . . . . 118
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Four Corner Air Suspension . . . . . . . . . . . . . 117
Four-Wheel-Drive . . . . . . . . . . . . . . . . . . . . . . . 114
Front Fog Lamp . . . . . . . . . . . . . . . . . . . . . . . . . 119
High-Beam On . . . . . . . . . . . . . . . . . . . . . . . . . . 119
High/Low Beam Changer . . . . . . . . . . . . . . 136
Hill Descent Control . . . . . . . . . . . . . . . . . . . . 114
Lane Keep Assist . . . . . . . . . . . . . . . . . . . . . . . . 114
Low Fuel Warning . . . . . . . . . . . . . . . . . . . . . . 118
Seat Belt Reminders . . . . . . . . . . . . . . . . . . . 109
Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./Cana-
da/Mexico-13690468) - 2021 - crc - 8/14/20
424 Index
Lights (cont'd)Service Electric Parking Brake . . . . . . . . . . . 113
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Traction Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Lock Steering Column . . . . . . . . . . . . . . . . . . . . . . . . 27
Locking Rear Axle . . . . . . . . . . . . . . . . . . . . . . . . 248
Locks
Automatic Door . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Delayed Locking . . . . . . . . . . . . . . . . . . . . . . . . . 17
Door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Lockout Protection . . . . . . . . . . . . . . . . . . . . . . . 17
Power Door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Loss of Control . . . . . . . . . . . . . . . . . . . . . . . . . . 216
Low Fuel Warning Light . . . . . . . . . . . . . . . . . . 118
Low-Profile Tires . . . . . . . . . . . . . . . . . . . . . . . . . 340
Lower Anchors and Tethers for Children (LATCH System) . . . . . . . . . . . . . . . . .77
Lumbar Adjustment . . . . . . . . . . . . . . . . . . . . . . . 40 Front Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
M
Magnetic Ride Control . . . . . . . . . . . . . . . . . . . 247
MaintenanceRecords . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 395 Maintenance and Care
Additional . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 390
Maintenance Schedule . . . . . . . . . . . . . . . . . . . 384 Recommended Fluids andLubricants . . . . . . . . . . . . . . . . . . . . . . . . . . . . 392
Transfer Case . . . . . . . . . . . . . . . . . . . . . . . . . . 236
Malfunction Indicator Lamp . . . . . . . . . . . . . . . 111
Manual Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . 235
Map Data Updates . . . . . . . . . . . . . . . . . . . . . . . . 175
Maps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
Media
Avoiding Untrusted Devices . . . . . . . . . . . . . 151
Memory Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
Messages Engine Power . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Vehicle Speed . . . . . . . . . . . . . . . . . . . . . . . . . . 126
Mirror Rear Camera . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Mirrors Automatic Dimming . . . . . . . . . . . . . . . . . . . . 30
Automatic Dimming Rearview . . . . . . . . . . 30
Convex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Folding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Heated . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Manual Rearview . . . . . . . . . . . . . . . . . . . . . . . 30
Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Tilt in Reverse . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Mirrors, Interior Rearview . . . . . . . . . . . . . . . . . 30
Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245
Driver Control . . . . . . . . . . . . . . . . . . . . . . . . . 245
Monitor System, Tire Pressure . . . . . . . . . . . 346
Multi-band Antenna . . . . . . . . . . . . . . . . . . . . . . 151
N
Navigation Connected Services . . . . . . . . . . . . . . . . . . . . 415
Destination . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168
Using the System . . . . . . . . . . . . . . . . . . . . . . 164
Navigation Symbols . . . . . . . . . . . . . . . . . . . . . 167
Net, Convenience . . . . . . . . . . . . . . . . . . . . . . . . . 93
New Vehicle Break-In . . . . . . . . . . . . . . . . . . . . 226
O
Odometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Trip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Off-Road . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216 Driving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216
Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Oil
Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315
Engine Oil Life System . . . . . . . . . . . . . . . . . 316
Engine Oil Pressure Gauge . . . . . . . . . . . . . 107
Pressure Light . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Older Children, Restraints . . . . . . . . . . . . . . . . . . 71
Online Owner Center . . . . . . . . . . . . . . . . . . . . 401
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 409

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./Cana-
da/Mexico-13690468) - 2021 - crc - 8/14/20
Index 429
Warning (cont'd)Caution and Danger . . . . . . . . . . . . . . . . . . . . . 2
Warning Lights, Gauges, and Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
Warnings Hazard Flashers . . . . . . . . . . . . . . . . . . . . . . . . . 137
Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . 324
Wheels
Alignment and Tire Balance . . . . . . . . . . . . 354
Different Size . . . . . . . . . . . . . . . . . . . . . . . . . . 352
Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . 354
When It Is Time for New Tires . . . . . . . . . . . . 351
Where to Put the Restraint . . . . . . . . . . . . . . . 76
Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Windshield
Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . 330
Wiper/Washer . . . . . . . . . . . . . . . . . . . . . . . . . . 97
Winter Driving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 340
Wiper Blade Replacement . . . . . . . . . . . . . . . . 329
Wipers
Rear Washer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Wireless Charging . . . . . . . . . . . . . . . . . . . . . . . .101