ECO mode GMC SIERRA 2020 Service Manual

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
Customer Information 471
Insuring the Vehicle
Protect your investment in the GM
vehicle with comprehensive and
collision insurance coverage. There
are significant differences in the
quality of coverage afforded by
various insurance policy terms.
Many insurance policies provide
reduced protection to the GM
vehicle by limiting compensation for
damage repairs through the use of
aftermarket collision parts. Some
insurance companies will not
specify aftermarket collision parts.
When purchasing insurance, we
recommend that you ensure that the
vehicle will be repaired with GM
original equipment collision parts.
If such insurance coverage is not
available from your current
insurance carrier, consider switching
to another insurance carrier.
If the vehicle is leased, the leasing
company may require you to have
insurance that ensures repairs with
Genuine GM Original Equipment
Manufacturer (OEM) parts or
Genuine Manufacturer replacementparts. Read the lease carefully, as
you may be charged at the end of
the lease for poor quality repairs.
If a Crash Occurs
If there has been an injury, call
emergency services for help. Do not
leave the scene of a crash until all
matters have been taken care of.
Move the vehicle only if its position
puts you in danger, or you are
instructed to move it by a police
officer.
Give only the necessary information
to police and other parties involved
in the crash.
For emergency towing see
Roadside Assistance Program
0
467.
Gather the following information:
. Driver name, address, and
telephone number
. Driver license number
. Owner name, address, and
telephone number
. Vehicle license plate number .
Vehicle make, model, and
model year
. Vehicle Identification
Number (VIN)
. Insurance company and policy
number
. General description of the
damage to the other vehicle
Choose a reputable repair facility
that uses quality replacement parts.
See “Collision Parts” earlier in this
section.
If the airbag has inflated, see What
Will You See after an Airbag
Inflates? 077.
Managing the Vehicle Damage
Repair Process
In the event that the vehicle requires
damage repairs, GM recommends
that you take an active role in its
repair. If you have a pre-determined
repair facility of choice, take the
vehicle there, or have it towed there.
Specify to the facility that any
required replacement collision parts
be original equipment parts, either
new Genuine GM parts or recycled

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13337776) - 2020 - CRC - 4/4/19
Index 491
DiagnosticsConnected Services . . . . . . . . . . 487
Differential, Limited-Slip . . . . . . . . 242
Distracted Driving . . . . . . . . . . . . . . . 187
Dome Lamps . . . . . . . . . . . . . . . . . . . 172
Door Ajar Light . . . . . . . . . . . . . . . . . . . . . 148
Delayed Locking . . . . . . . . . . . . . . . . 26
Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Power Locks . . . . . . . . . . . . . . . . . . . . 26
Drive Belt Routing, Engine . . . . . . 462
Driver Assistance Systems . . . . . 256
Driver Information
Center (DIC) . . . . . . . . . . . . . 148, 149
Driver Mode Control . . . . . . . . . . . . 238
Driver Mode Control Light . . . . . . 145
Driving Assistance Systems . . . . . . . . . . 268
Better Fuel Economy . . . . . . . . . 186
Characteristics andTowing Tips . . . . . . . . . . . . . . . . . 287
Defensive . . . . . . . . . . . . . . . . . . . . . 187
Drunk . . . . . . . . . . . . . . . . . . . . . . . . . 188
Hill and Mountain Roads . . . . . . 197
If the Vehicle is Stuck . . . . . . . . . 199
Loss of Control . . . . . . . . . . . . . . . 190
Off-Road . . . . . . . . . . . . . . . . . . . . . 191
Off-Road Recovery . . . . . . . . . . . 190 Driving (cont'd)
Vehicle Load Limits . . . . . . . . . . . 200
Wet Roads . . . . . . . . . . . . . . . . . . . 196
Winter . . . . . . . . . . . . . . . . . . . . . . . . 197
Dual Automatic Climate Control System . . . . . . . . . . . . . . . . 179
E
E85 or FlexFuel . . . . . . . . . . . . . . . . 282
Electric Brake Boost . . . . . . . . . . . . 232
Electric Parking Brake . . . . . . . . . . 233
Electric Parking Brake Light . . . . 141
Electrical Equipment,Add-On . . . . . . . . . . . . . . . . . . . . . . . 322
Electrical System Engine Compartment FuseBlock . . . . . . . . . . . . . . . . . . . . . . . . 371
Fuses and Circuit Breakers . . . 370
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . 374, 376
Overload . . . . . . . . . . . . . . . . . . . . . 370
Electronic Stability Control (ESC) Off Light . . . . . . . . . . . . . . . . 144
Emergency
OnStar . . . . . . . . . . . . . . . . . . . . . . . 478
Engine Air Cleaner/Filter . . . . . . . . . . . . . 344 Engine (cont'd)
Check Light (Malfunction
Indicator) . . . . . . . . . . . . . . . . . . . . 138
Compartment Overview . . . . . . . 332
Coolant Temperature
Gauge . . . . . . . . . . . . . . . . . . . . . . 134
Coolant Temperature Warning Light . . . . . . . . . . . . . . . 145
Cooling System . . . . . . . . . . . . . . . 346
Drive Belt Routing . . . . . . . . . . . . 462
Exhaust . . . . . . . . . . . . . . . . . . . . . . 220
Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . 353
Heater . . . . . . . . . . . . . . . . . . . . . . . . 215
Oil Life System . . . . . . . . . . . . . . . 341
Oil Pressure Gauge . . . . . . . . . . 133
Oil Pressure Light . . . . . . . . . . . . 146
Overheated Protection Operating Mode . . . . . . . . . . . . . 352
Overheating . . . . . . . . . . . . . . . . . . 351
Power Messages . . . . . . . . . . . . . 156
Running While Parked . . . . . . . . 220
Starting . . . . . . . . . . . . . . . . . . . . . . . 212
Engine Air Filter Life System . . . . 343
Entry Lighting . . . . . . . . . . . . . . . . . . . 173
Equipment, Towing . . . . . . . . . . . . . 296
Event Data Recorders . . . . . . . . . . 475
Exit Lighting . . . . . . . . . . . . . . . . . . . . 173
Extended Parking . . . . . . . . . . . . . . . 219

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13337776) - 2020 - CRC - 4/4/19
494 Index
Lamps (cont'd)On Reminder . . . . . . . . . . . . . . . . . 147
Reading . . . . . . . . . . . . . . . . . . . . . . 173
Lane Change Alert (LCA) . . . . . . . 274
Lane Departure
Warning (LDW) . . . . . . . . . . . . . . . . 276
Lane Departure Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . 142
Lane Keep Assist (LKA) . . . . . . . . 278
Lane Keep Assist Light . . . . . . . . . 143
Lap-Shoulder Belt . . . . . . . . . . . . . . . 68
LATCH System
Replacing Parts after aCrash . . . . . . . . . . . . . . . . . . . . . . . 105
LATCH, Lower Anchors and Tethers for Children . . . . . . . . . . . . 92
LED Lighting . . . . . . . . . . . . . . . . . . . . 367
Lighting Entry . . . . . . . . . . . . . . . . . . . . . . . . . 173
Exit . . . . . . . . . . . . . . . . . . . . . . . . . . . 173
Illumination Control . . . . . . . . . . . 172
LED . . . . . . . . . . . . . . . . . . . . . . . . . . 367
Task . . . . . . . . . . . . . . . . . . . . . . . . . . 171
Lights Airbag Readiness . . . . . . . . . . . . . 136
Antilock Brake System(ABS) Warning . . . . . . . . . . . . . . 141
Brake System Warning . . . . . . . 140 Lights (cont'd)
Charging System . . . . . . . . . . . . . 138
Check Engine (Malfunction
Indicator) . . . . . . . . . . . . . . . . . . . . 138
Cruise Control . . . . . . . . . . . . . . . . 147
Door Ajar . . . . . . . . . . . . . . . . . . . . . 148
Driver Mode Control . . . . . . . . . . 145
Electric Parking Brake . . . . . . . . 141
Electronic Stability Control (ESC), Off . . . . . . . . . . . . . . . . . . . 144
Engine Coolant Temperature Warning . . . . . . . 145
Engine Oil Pressure . . . . . . . . . . 146
Flash-to-Pass . . . . . . . . . . . . . . . . . 168
Four-Wheel-Drive . . . . . . . . . . . . . 142
Front Fog Lamp . . . . . . . . . . . . . . 147
High-Beam On . . . . . . . . . . . . . . . . 147
High/Low Beam Changer . . . . . 167
Hill Descent Control . . . . . . . . . . 142
Lane Departure Warning . . . . . . 142
Lane Keep Assist . . . . . . . . . . . . . 143
Low Fuel Warning . . . . . . . . . . . . 146
Seat Belt Reminders . . . . . . . . . . 136
Security . . . . . . . . . . . . . . . . . . . . . . 147
Service Electric Parking Brake . . . . . . . . . . . . . . . . . . . . . . . 141
Tire Pressure . . . . . . . . . . . . . . . . . 145
Tow/Haul Mode . . . . . . . . . . . . . . . 142 Lights (cont'd)
Traction Off . . . . . . . . . . . . . . . . . . . 143
Limited-Slip Differential . . . . . . . . . 242
Lock Steering Column . . . . . . . . . . . . . . . . 38
Locking Rear Axle . . . . . . . . . . . . . . 243
Locks Automatic Door . . . . . . . . . . . . . . . . . 26
Delayed Locking . . . . . . . . . . . . . . . . 26
Door . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Lockout Protection . . . . . . . . . . . . . . 27
Power Door . . . . . . . . . . . . . . . . . . . . . 26
Safety . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Loss of Control . . . . . . . . . . . . . . . . . 190
Low Fuel Warning Light . . . . . . . . . 146
Low-Profile Tires . . . . . . . . . . . . . . . . 380
Lower Anchors and Tethers for Children (LATCH
System) . . . . . . . . . . . . . . . . . . . . . . . . 92
Lumbar Adjustment . . . . . . . . . . . . . . 57 Front Seats . . . . . . . . . . . . . . . . . . . . . 57
M
MaintenanceRecords . . . . . . . . . . . . . . . . . . . . . . 457
Maintenance and Care Additional . . . . . . . . . . . . . . . . . . . . . 450
Maintenance Schedule . . . . . . . . . 442

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13337776) - 2020 - CRC - 4/4/19
Index 495
Maintenance Schedule (cont'd)Recommended Fluids and
Lubricants . . . . . . . . . . . . . . . . . . . 453
Transfer Case . . . . . . . . . . . . . . . . 227
Malfunction Indicator Lamp . . . . . 138
Manual Mirrors . . . . . . . . . . . . . . . . . . 41
Manual Mode . . . . . . . . . . . . . . . . . . . 224
Manual Windows . . . . . . . . . . . . . . . . 49
Memory Seats . . . . . . . . . . . . . . . . . . . 59
Messages Engine Power . . . . . . . . . . . . . . . . 156
Vehicle . . . . . . . . . . . . . . . . . . . . . . . 156
Vehicle Speed . . . . . . . . . . . . . . . . 156
Mirror
Rear Camera . . . . . . . . . . . . . . . . . . . 46
Mirrors Automatic Dimming . . . . . . . . . . . . . 44
Automatic DimmingRearview . . . . . . . . . . . . . . . . . . . . . . 46
Blind Spot . . . . . . . . . . . . . . . . . . . . . . 44
Convex . . . . . . . . . . . . . . . . . . . . . . . . . 40
Folding . . . . . . . . . . . . . . . . . . . . . . . . . 43
Heated . . . . . . . . . . . . . . . . . . . . . . . . . 44
Manual . . . . . . . . . . . . . . . . . . . . . . . . . 41
Manual Rearview . . . . . . . . . . . . . . . 46
Power . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Tilt in Reverse . . . . . . . . . . . . . . . . . . 45
Trailer Tow . . . . . . . . . . . . . . . . . . . . . . 41 Mirrors, Interior Rearview . . . . . . . . 46
Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . 238
Driver Control . . . . . . . . . . . . . . . . . 238
Monitor System, Tire Pressure . . . . . . . . . . . . . . . . . . . . . . 389
N
NavigationConnected Services . . . . . . . . . . 485
New Vehicle Break-In . . . . . . . . . . . 208
Noise Control System . . . . . . . . . . 362
O
Odometer . . . . . . . . . . . . . . . . . . . . . . . 132 Trip . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
Off-Road . . . . . . . . . . . . . . . . . . . . . . . 191 Driving . . . . . . . . . . . . . . . . . . . . . . . . 191
Recovery . . . . . . . . . . . . . . . . . . . . . 190
Oil Engine . . . . . . . . . . . . . . . . . . . . . . . . 339
Engine Oil Life System . . . . . . . 341
Engine Oil Pressure Gauge . . . 133
Pressure Light . . . . . . . . . . . . . . . . 146
Older Children, Restraints . . . . . . . 85
Online Owner Center . . . . . . . . . . . 466
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . 476
OnStar Additional Information . . . . . . . . . . . . . . . . . . . . 479
OnStar Emergency . . . . . . . . . . . . . 478 OnStar Overview . . . . . . . . . . . . . . . 477
OnStar Security . . . . . . . . . . . . . . . . 479
Operating Mode
Overheated EngineProtection . . . . . . . . . . . . . . . . . . . 352
Operation Fog Lamps . . . . . . . . . . . . . . . . . . . 170
Outlets Power . . . . . . . . . . . . . . . . . . . . . . . . 122
Overheated Engine Protection Operating Mode . . . . 352
Overheating, Engine . . . . . . . . . . . . 351
Overview Instrument Panel . . . . . . . . . . . . . . . . 5
P
ParkShifting Out of . . . . . . . . . . . . . . . . 218
Park Assist . . . . . . . . . . . . . . . . . . . . . 257
Parking Brake and P (Park)
Mechanism Check . . . . . . . . . . 364
Extended . . . . . . . . . . . . . . . . . . . . . 219
Over Things That Burn . . . . . . . 219
Parking or Backing Assistance Systems . . . . . . . . . . 257
Passenger Airbag Status Indicator . . . . . . . . . . . . . . . . . . . . . . 137