2020 GMC TERRAIN check engine light

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13556230) - 2020 - CRC - 9/4/19
Driving and Operating 271
Trailer Lamps
Always check all trailer lamps are
working at the beginning of each
trip, and periodically on longer trips.
Turn Signals When Towing a
Trailer
When properly connected, the trailer
turn signals will illuminate to indicate
the vehicle is turning, changing
lanes, or stopping. When towing a
trailer, the arrows on the instrument
cluster will illuminate even if the
trailer is not properly connected or
the bulbs are burned out.
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.
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).
Conversions and
Add-Ons
Add-On Electrical
Equipment
{Warning
The Data Link Connector (DLC) is
used for vehicle service and
Emission Inspection/Maintenance
testing. See
Malfunction Indicator
Lamp (Check Engine Light) 0115.
A device connected to the DLC —
such as an aftermarket fleet or
driver-behavior tracking device —
may interfere with vehicle
systems. This could affect vehicle
operation and cause a crash.
Such devices may also access
information stored in the vehicle’s
systems.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13556230) - 2020 - CRC - 9/5/19
Vehicle Care 273
Vehicle Care
General Information
General Information . . . . . . . . . . 274
California Proposition65 Warning . . . . . . . . . . . . . . . . . 274
California Perchlorate Materials Requirements . . . . . 275
Accessories and Modifications . . . . . . . . . . . . . . . . 275
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 275
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 276
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 278
Engine Oil . . . . . . . . . . . . . . . . . . . . 283
Engine Oil Life System . . . . . . . 287
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 288
Engine Air Cleaner/Filter . . . . . . 288
Cooling System . . . . . . . . . . . . . . 290
Engine Overheating . . . . . . . . . . 294
Washer Fluid . . . . . . . . . . . . . . . . . 296
Brakes . . . . . . . . . . . . . . . . . . . . . . . 296
Brake Fluid . . . . . . . . . . . . . . . . . . . 297
Battery - North America . . . . . . 298
All-Wheel Drive . . . . . . . . . . . . . . . 299 Starter Switch Check . . . . . . . . . 299
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . 300
Wiper Blade Replacement . . . . 300
Windshield Replacement . . . . . 301
Gas Strut(s) . . . . . . . . . . . . . . . . . . 302
Headlamp Aiming
Front Headlamp Aiming . . . . . . 303
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 303
Halogen Bulbs . . . . . . . . . . . . . . . . 303
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . 304
LED Lighting . . . . . . . . . . . . . . . . . 304
Front Turn Signal Lamps . . . . . 304
Taillamps . . . . . . . . . . . . . . . . . . . . . 304
License Plate Lamp . . . . . . . . . . 305
Electrical System
Electrical System Overload . . . 306
Fuses and Circuit Breakers . . . 307
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 307
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 310
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 312
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 314
All-Season Tires . . . . . . . . . . . . . . 315
Winter Tires . . . . . . . . . . . . . . . . . . 315
Summer Tires . . . . . . . . . . . . . . . . 316
Tire Sidewall Labeling . . . . . . . . 316
Tire Designations . . . . . . . . . . . . . 318
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 319
Tire Pressure . . . . . . . . . . . . . . . . . 321
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 323
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . 324
Tire Inspection . . . . . . . . . . . . . . . . 328
Tire Rotation . . . . . . . . . . . . . . . . . 328
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . 329
Buying New Tires . . . . . . . . . . . . . 330
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . 331
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . . . 332
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . 333
Wheel Replacement . . . . . . . . . . 333
Tire Chains . . . . . . . . . . . . . . . . . . . 334
If a Tire Goes Flat . . . . . . . . . . . . 335
Tire Sealant and Compressor Kit . . . . . . . . . . . . . 336

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13556230) - 2020 - CRC - 9/5/19
288 Vehicle Care
2. Display REMAINING OIL LIFEon the DIC menu. See Driver
Information Center (DIC) (Base
and Midlevel) 0124 or
Driver Information Center (DIC)
(Uplevel) 0130.
3. Fully press and release the accelerator pedal three times
within five seconds.
4. If the display changes to 100%, the system is reset.
If the CHANGE ENGINE OIL SOON
message comes back on when the
vehicle is started, the engine oil life
system has not reset. Repeat the
procedure.
Automatic Transmission
Fluid
It is not necessary to check the
transmission fluid level.
A transmission fluid leak is the only
reason for fluid loss. If a leak
occurs, take the vehicle to your
dealer and have it repaired as soon
as possible. Change the fluid at the intervals
listed in
Maintenance Schedule
0 368, and be sure to use the
transmission fluid listed in
Recommended Fluids and
Lubricants 0377.
Caution
Use of the incorrect automatic
transmission fluid may damage
the vehicle, and the damage may
not be covered by the vehicle
warranty. Always use the correct
automatic transmission fluid. See
Recommended Fluids and
Lubricants 0377.
There is a special procedure for
checking and changing the
transmission fluid. Because this
procedure is difficult, this should be
done by your dealer.
Engine Air Cleaner/Filter
The engine air cleaner/filter is in the
engine compartment on the
passenger side of the vehicle. See
Engine Compartment Overview
0 278.
When to Inspect the Engine Air
Cleaner/Filter
For intervals on changing and
inspecting the engine air cleaner/
filter, see Maintenance Schedule
0 368.
How to Inspect the Engine Air
Cleaner/Filter
Do not start the engine or have the
engine running with the engine air
cleaner/filter housing open. Before
removing the engine air cleaner/
filter, make sure that the engine air
cleaner/filter housing and nearby
components are free of dirt and
debris. Remove the engine air
cleaner/filter. Lightly tap and shake
the engine air cleaner/filter (away
from the vehicle), to release loose
dust and dirt. Inspect the engine air
cleaner/filter for damage, and

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13556230) - 2020 - CRC - 9/5/19
Vehicle Care 297
Caution
Continuing to drive with worn-out
brake pads could result in costly
brake repair.
Some driving conditions or climates
can cause a brake squeal when the
brakes are first applied or lightly
applied. This does not mean
something is wrong with the brakes.
Properly torqued wheel nuts are
necessary to help prevent brake
pulsation. When tires are rotated,
inspect brake pads for wear and
evenly tighten wheel nuts in the
proper sequence to torque
specifications. See Capacities and
Specifications 0382.
Brake pads should be replaced as
complete sets.
Brake Pedal Travel
See your dealer if the brake pedal
does not return to normal height,
or if there is a rapid increase in
pedal travel. This could be a sign
that brake service may be required.
Replacing Brake System Parts
Always replace brake system parts
with new, approved replacement
parts. If this is not done, the brakes
may not work properly. The braking
performance expected can change
in many other ways if the wrong
replacement brake parts are
installed or if parts are improperly
installed.
Brake Fluid
The brake master cylinder reservoir
is filled with GM approved DOT 3
brake fluid as indicated on the
reservoir cap. See Engine
Compartment Overview 0278 for
the location of the reservoir. Checking Brake Fluid
With the vehicle in P (Park) on a
level surface, the brake fluid level
should be between the minimum
and maximum marks on the brake
fluid reservoir.
There are only two reasons why the
brake fluid level in the reservoir may
go down:
.
Normal brake lining wear. When
new linings are installed, the
fluid level goes back up.
. A fluid leak in the brake
hydraulic system. Have the
brake hydraulic system fixed.
With a leak, the brakes will not
work well.
Always clean the brake fluid
reservoir cap and the area around
the cap before removing it.
Do not top off the brake fluid.
Adding fluid does not correct a leak.
If fluid is added when the linings are
worn, there will be too much fluid
when new brake linings are

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13556230) - 2020 - CRC - 9/4/19
Service and Maintenance 375
.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 0377 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. Lamps
Properly working headlamps,
taillamps, and brake lamps are
important to see and be seen on
the road.
.
Signs that the headlamps need
attention include dimming, failure
to light, cracking, or damage.
The brake lamps need to be
checked periodically to ensure
that they light when braking.
. With a multi-point inspection,
your dealer can check the lamps
and note any concerns.
Shocks and Struts
Shocks and struts help aid in control
for a smoother ride.
. Signs of wear may include
steering wheel vibration, bounce/
sway while braking, longer
stopping distance, or uneven
tire wear.
. As part of the multi-point
inspection, trained dealer
technicians can visually inspect
the shocks and struts for signs of leaking, blown seals,
or damage, and can advise
when service is needed.
Tires
Tires need to be properly inflated,
rotated, and balanced. Maintaining
the tires can save money and fuel,
and can reduce the risk of tire
failure.
. Signs that the tires need to be
replaced include three or more
visible treadwear indicators; cord
or fabric showing through the
rubber; cracks or cuts in the
tread or sidewall; or a bulge or
split in the tire.
. Trained dealer technicians can
inspect and recommend the right
tires. Your dealer can also
provide tire/wheel balancing
services to ensure smooth
vehicle operation at all speeds.
Your dealer sells and services
name brand tires.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13556230) - 2020 - CRC - 9/4/19
410 Index
IndexA
About Driving the Vehicle . . . . . . . . . 3
Accessories andModifications . . . . . . . . . . . . . . . . . . 275
Accessory Power . . . . . . . . . . . . . . . 187
Adaptive Cruise Control . . . . . . . . 219
Add-On Electrical Equipment . . . 271
Additional Information
OnStar . . . . . . . . . . . . . . . . . . . . . . . 401
Additional Maintenance
and Care . . . . . . . . . . . . . . . . . . . . . . 374
Adjustments Lumbar, Front Seats . . . . . . . . . . . . 40
Air Cleaner/Filter, Engine . . . . . . . 288
Air Conditioning . . . . . . . . . . . 153, 155
Air Filter, Passenger
Compartment . . . . . . . . . . . . . . . . . 158
Air Vents . . . . . . . . . . . . . . . . . . . . . . . 158
Airbag System Check . . . . . . . . . . . . . . . . . . . . . . . . . . 70
How Does an AirbagRestrain? . . . . . . . . . . . . . . . . . . . . . 63
Passenger Sensing System . . . . 64
What Makes an Airbag Inflate? . . . . . . . . . . . . . . . . . . . . . . . . 62 Airbag System (cont'd)
What Will You See after an
Airbag Inflates? . . . . . . . . . . . . . . . 63
When Should an Airbag
Inflate? . . . . . . . . . . . . . . . . . . . . . . . . 62
Where Are the Airbags? . . . . . . . . 60
Airbags Adding Equipment to theVehicle . . . . . . . . . . . . . . . . . . . . . . . . 69
Passenger Status Indicator . . . .114
Readiness Light . . . . . . . . . . . . . . .113
Servicing Airbag-Equipped Vehicles . . . . . . . . . . . . . . . . . . . . . . . 68
System Check . . . . . . . . . . . . . . . . . . 58
Alarm Vehicle Security . . . . . . . . . . . . . . . . 27
Alert Lane Change . . . . . . . . . . . . . . . . . 243
Side Blind Zone (SBZA) . . . . . . 243
All-Season Tires . . . . . . . . . . . . . . . . 315
All-Wheel Drive . . . . . . . . . . . . 206, 299
Antilock Brake System (ABS) . . . 206 Warning Light . . . . . . . . . . . . . . . . . .118
Appearance Care Exterior . . . . . . . . . . . . . . . . . . . . . . . 356
Interior . . . . . . . . . . . . . . . . . . . . . . . . 361

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13556230) - 2020 - CRC - 9/4/19
412 Index
CheckEngine Light (Malfunction
Indicator) . . . . . . . . . . . . . . . . . . . . .115
Child Restraints Infants and Young Children . . . . . 72
Lower Anchors and Tethersfor Children . . . . . . . . . . . . . . . . . . . 77
Older Children . . . . . . . . . . . . . . . . . . 70
Securing . . . . . . . . . . . . . . . . . . . . 85, 87
Systems . . . . . . . . . . . . . . . . . . . . . . . . 74
Circuit Breakers . . . . . . . . . . . . . . . . 307
Cleaning
Exterior Care . . . . . . . . . . . . . . . . . 356
Interior Care . . . . . . . . . . . . . . . . . . 361
Climate Control Systems . . . . . . . 153 Air Conditioning . . . . . . . . . . . . . . 153
Dual Automatic . . . . . . . . . . . . . . . 155
Heating . . . . . . . . . . . . . . . . . . . . . . . 153
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Cluster, Instrument . . . . . . . . 103, 107
Cold Weather Operation . . . . . . . . 252
Collision Damage Repair . . . . . . . 392
Compact Spare Tire . . . . . . . . . . . . 348
Compartments Storage . . . . . . . . . . . . . . . . . . . . . . . . . 90
Compass . . . . . . . . . . . . . . . . . . . . . . . . 97
Compressor Kit, Tire Sealant . . . 336 Connected Services
Connections . . . . . . . . . . . . . . . . . . 408
Diagnostics . . . . . . . . . . . . . . . . . . . 409
Navigation . . . . . . . . . . . . . . . . . . . . 407
Connections Connected Services . . . . . . . . . . 408
Control
Hill Descent . . . . . . . . . . . . . . . . . . 213
Traction and ElectronicStability . . . . . . . . . . . . . . . . . . . . . 209
Control Light
Hill Descent . . . . . . . . . . . . . . . . . . .119
Control of a Vehicle . . . . . . . . . . . . . 165
Convenience Net . . . . . . . . . . . . . . . . 92
Convex Mirrors . . . . . . . . . . . . . . . . . . 29
Coolant Engine Temperature Gauge . . .112
Cooling . . . . . . . . . . . . . . . . . . . . 153, 155
Cooling System . . . . . . . . . . . . . . . . . 290
Courtesy Lamps . . . . . . . . . . . . . . . . 149
Courtesy Transportation Program . . . . . . . . . . . . . . . . . . . . . . . 391
Cover Cargo . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Covers
Winter . . . . . . . . . . . . . . . . . . . . . . . . 185
Cruise Control . . . . . . . . . . . . . . . . . . 217 Light . . . . . . . . . . . . . . . . . . . . . . . . . . 124 Cruise Control, Adaptive . . . . . . . . 219
Cupholders . . . . . . . . . . . . . . . . . . . . . . 90
Customer Assistance . . . . . . . . . . . 388
Offices . . . . . . . . . . . . . . . . . . . . . . . . 387
Text Telephone (TTY)Users . . . . . . . . . . . . . . . . . . . . . . . 388
Customer Information
Publications OrderingInformation . . . . . . . . . . . . . . . . . . 394
Customer Satisfaction Procedure . . . . . . . . . . . . . . . . . . . . . 385
Cybersecurity . . . . . . . . . . . . . . . . . . . 397
D
Damage Repair, Collision . . . . . . . 392
Danger, Warning, and Caution . . . . 3
Data Collection Infotainment System . . . . . . . . . . 398
OnStar . . . . . . . . . . . . . . . . . . . . . . . 398
Data Recorders, Event . . . . . . . . . 397
Daytime Running Lamps (DRL) . . . . . . . . . . . . . . . . . . 146
Defensive Driving . . . . . . . . . . . . . . . 164
Delayed Locking . . . . . . . . . . . . . . . . . 19
Diagnostics Connected Services . . . . . . . . . . 409
Diesel Exhaust Fluid . . . . . . . . . . . . 195

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13556230) - 2020 - CRC - 9/4/19
Index 413
Diesel Exhaust Fluid (DEF)Warning Light . . . . . . . . . . . . . . . . . 122
Diesel Particulate Filter . . . . . . . . . 192
Distracted Driving . . . . . . . . . . . . . . . 163
Dome Lamps . . . . . . . . . . . . . . . . . . . 149
Door Ajar Light . . . . . . . . . . . . . . . . . . . . . 124
Delayed Locking . . . . . . . . . . . . . . . . 19
Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Power Locks . . . . . . . . . . . . . . . . . . . . 19
Drive Belt Routing, Engine . . . . . . 384
Drive Systems
All-Wheel Drive . . . . . . . . . . 206, 299
Driver Assistance Systems . . . . . 230
Driver Behavior . . . . . . . . . . . . . . . . . 162
Driver Information Center (DIC) . . . . . . . . . . . . . 124, 130
Driver Mode Control . . . . . . . . . . . . 214
Driving Assistance Systems . . . . . . . . . . 237
Better Fuel Economy . . . . . . . . . 163
Characteristics andTowing Tips . . . . . . . . . . . . . . . . . 262
Defensive . . . . . . . . . . . . . . . . . . . . . 164
Drunk . . . . . . . . . . . . . . . . . . . . . . . . . 164
Environment . . . . . . . . . . . . . . . . . . 163
Hill and Mountain Roads . . . . . . 172
If the Vehicle is Stuck . . . . . . . . . 174 Driving (cont'd)
Loss of Control . . . . . . . . . . . . . . . 167
Off-Road . . . . . . . . . . . . . . . . . . . . . 167
Off-Road Recovery . . . . . . . . . . . 166
Vehicle Load Limits . . . . . . . . . . . 175
Wet Roads . . . . . . . . . . . . . . . . . . . 171
Winter . . . . . . . . . . . . . . . . . . . . . . . . 173
Driving the Vehicle . . . . . . . . . . . . . . . . 3
Dual Automatic Climate Control System . . . . . . . . . . . . . . . . 155
E
Electric Parking Brake . . . . . . . . . . 207
Electric Parking Brake Light . . . . 118
Electrical Equipment,Add-On . . . . . . . . . . . . . . . . . . . . . . . 271
Electrical System Engine Compartment FuseBlock . . . . . . . . . . . . . . . . . . . . . . . . 307
Fuses and Circuit Breakers . . . 307
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 310
Overload . . . . . . . . . . . . . . . . . . . . . 306
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 312
Emergency OnStar . . . . . . . . . . . . . . . . . . . . . . . 400 Engine
Air Cleaner/Filter . . . . . . . . . . . . . 288
Check Light (Malfunction
Indicator) . . . . . . . . . . . . . . . . . . . . .115
Compartment Overview . . . . . . . 278
Coolant Temperature Gauge . . . . . . . . . . . . . . . . . . . . . . .112
Cooling System . . . . . . . . . . . . . . . 290
Drive Belt Routing . . . . . . . . . . . . 384
Exhaust . . . . . . . . . . . . . . . . . . . . . . 191
Heater . . . . . . . . . . . . . . . . . . . . . . . . 186
Oil Life System . . . . . . . . . . . . . . . 287
Oil Pressure Light . . . . . . . . . . . . 122
Overheating . . . . . . . . . . . . . . . . . . 294
Power Messages . . . . . . . . . . . . . 134
Running While Parked . . . . . . . . 192
Starting . . . . . . . . . . . . . . . . . . . . . . . 181
Engines Diesel Fuel . . . . . . . . . . . . . . . . . . . 250
Entry Lighting . . . . . . . . . . . . . . . . . . . 150
Equipment, Towing . . . . . . . . . . . . . 269
Event Data Recorders . . . . . . . . . . 397
Exhaust Fluid Diesel . . . . . . . . . . . . . . . . . . . . . . . . 195
Exit Lighting . . . . . . . . . . . . . . . . . . . . 150
Extended Parking . . . . . . . . . . . . . . . 190
Extender, Seat Belt . . . . . . . . . . . . . . 57