2018 GMC TERRAIN check engine light

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-10664916) - 2018 - crc - 9/15/17
250 Driving and Operating
Caution (Continued)
of fuel cap may not fit properly,
may cause the malfunction
indicator lamp to light, and could
damage the fuel tank and
emissions system. See
Malfunction Indicator Lamp
(Check Engine Light)0127.
Diesel fuel can foam when filling the
tank. This can cause the automatic
pump nozzle to shut off, even if the
tank is not full. If this happens, wait
for the foaming to stop, and then fill
the tank more slowly.
{Warning
Heat coming from the engine can
cause the fuel to expand and
force the fuel out of the tank.
If something ignites the fuel, a fire
could start. To help avoid this, fill
the tank slowly and only until the
nozzle shuts off. Do not top it off.
Clean up any spilled fuel. Accidental Refueling with
Gasoline
If the vehicle is accidentally refueled
with gasoline, do not continue
driving the vehicle except to get to a
location where it can be stopped
safely. Driving the vehicle will
damage the fuel system. Have the
vehicle towed to a qualified
technician to have the gasoline
removed from the tank and fuel
system. Flush the fuel system with
Ultra Low Sulfur Diesel fuel to
ensure all gasoline is removed.
Diesel Exhaust Fluid (DEF)
DEF is a non-toxic solution that is
sprayed into the exhaust stream of
diesel vehicles to cause a chemical
reaction and break down NOx
emissions into harmless nitrogen
and water.
DEF is not a fuel additive and never
comes into contact with diesel fuel.
It is stored in a separate tank. The
fill port is behind the fuel door next
to the regular fuel cap. It has a blue
filler cap. See
Diesel Exhaust Fluid
0 198.
Filling a Portable Fuel
Container
{Warning
Filling a portable fuel container
while it is in the vehicle can cause
fuel vapors that can ignite either
by static electricity or other
means. You or others could be
badly burned and the vehicle
could be damaged. Always:
(Continued)

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-10664916) - 2018 - crc - 9/15/17
Driving and Operating 257
Safety Chains
Always attach chains between the
vehicle and the trailer. Cross the
safety chains under the tongue of
the trailer to help prevent the tongue
from contacting the road if it
becomes separated from the hitch.
Leave enough slack so the rig can
turn. Never allow safety chains to
drag on the ground.
Trailer Brakes
A loaded trailer that weighs more
than 454 kg (1,000 lb) must be
equipped with its own brake system,
with brakes working on all axles.
Trailer braking equipment
conforming to Canadian Standards
Association (CSA) requirement
CAN3-D313, or its equivalent, is
recommended. State and local
regulations may also require the
trailer to have its own braking
system if loaded above a certain
threshold. These requirements vary
from state to state. Read and follow
the instructions for the trailer brakes
so they are installed, adjusted, and
maintained properly.Do not tap into the vehicle's
hydraulic brake system.
Trailer Sway
Control (TSC)
The vehicle has a Trailer Sway
Control (TSC) feature as part of the
StabiliTrak system. If TSC detects
that the trailer is swaying, the
vehicle's brakes are automatically
applied.
When TSC is applying the brakes,
the TCS/StabiliTrak indicator light
flashes to notify the driver to reduce
speed. If the trailer continues to
sway, StabiliTrak will reduce engine
torque to help slow the vehicle.
TSC will not function if StabiliTrak is
turned off. See
Traction Control/
Electronic Stability Control 0213.
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) 0127.
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-10664916) - 2018 - crc - 9/15/17
Vehicle Care 259
Vehicle Care
General Information
General Information . . . . . . . . . . 260
California Proposition65 Warning . . . . . . . . . . . . . . . . . 260
California Perchlorate Materials Requirements . . . . . 261
Accessories and Modifications . . . . . . . . . . . . . . . . 261
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 261
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 262
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 264
Engine Oil . . . . . . . . . . . . . . . . . . . . 269
Engine Oil Life System . . . . . . . 273
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 274
Engine Air Cleaner/Filter . . . . . . 274
Cooling System . . . . . . . . . . . . . . 276
Engine Overheating . . . . . . . . . . 280
Washer Fluid . . . . . . . . . . . . . . . . . 282
Brakes . . . . . . . . . . . . . . . . . . . . . . . 282
Brake Fluid . . . . . . . . . . . . . . . . . . . 283
Battery - North America . . . . . . 284
All-Wheel Drive . . . . . . . . . . . . . . . 285 Starter Switch Check . . . . . . . . . 285
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . 286
Wiper Blade Replacement . . . . 286
Windshield Replacement . . . . . 287
Gas Strut(s) . . . . . . . . . . . . . . . . . . 287
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 289
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 289
Halogen Bulbs . . . . . . . . . . . . . . . . 289
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . 289
LED Lighting . . . . . . . . . . . . . . . . . 289
Front Turn Signal Lamps . . . . . 289
Taillamps . . . . . . . . . . . . . . . . . . . . . 290
License Plate Lamp . . . . . . . . . . 291
Electrical System
Electrical System Overload . . . 292
Fuses and Circuit Breakers . . . 292
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 293
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 296
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 298
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 300 All-Season Tires . . . . . . . . . . . . . . 301
Winter Tires . . . . . . . . . . . . . . . . . . 301
Summer Tires . . . . . . . . . . . . . . . . 302
Tire Sidewall Labeling . . . . . . . . 302
Tire Designations . . . . . . . . . . . . . 304
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . 305
Tire Pressure . . . . . . . . . . . . . . . . . 307
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 309
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . 310
Tire Inspection . . . . . . . . . . . . . . . . 313
Tire Rotation . . . . . . . . . . . . . . . . . 314
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . 315
Buying New Tires . . . . . . . . . . . . . 315
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . 317
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . . . 317
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . 319
Wheel Replacement . . . . . . . . . . 319
Tire Chains . . . . . . . . . . . . . . . . . . . 320
If a Tire Goes Flat . . . . . . . . . . . . 320
Tire Sealant and Compressor Kit . . . . . . . . . . . . . 322
Storing the Tire Sealant and Compressor Kit . . . . . . . . . . . . . 328

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-10664916) - 2018 - crc - 9/15/17
274 Vehicle Care
3. Fully press and release theaccelerator 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
How to Check 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.
There is a special procedure for
checking and changing the
transmission fluid. Because this
procedure is difficult, this should be
done at your dealer. Contact your dealer for additional information or
the procedure can be found in the
service manual. To purchase a
service manual, see
Service
Publications Ordering Information
0 378.
Change the fluid at the intervals
listed in Maintenance Schedule
0 353, and be sure to use the fluid
listed in Recommended Fluids and
Lubricants 0361.
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
0264.
When to Inspect the Engine Air
Cleaner/Filter
For intervals on changing and
inspecting the engine air cleaner/
filter, see Maintenance Schedule
0 353.
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
replace if damaged. Do not clean
the engine air cleaner/filter or
components with water or
compressed air.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-10664916) - 2018 - crc - 9/15/17
Vehicle Care 283
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 0366.
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 0264 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-10664916) - 2018 - crc - 9/15/17
336 Vehicle Care
3. Good Battery NegativeTerminal
4. Good Battery Positive Terminal
The jump start negative grounding
stud (1) for the discharged battery is
to the left of the windshield washer
fluid reservoir.
The jump start positive terminal on
the discharged battery (2) is located
in the engine compartment on the
driver side of the vehicle.
The jump start positive terminal (3)
and negative terminal (4) are on the
battery of the vehicle providing the
jump start.
The positive jump start connection
for the discharged battery is under a
trim cover. Open the cover to
expose the terminal.
1. Check the other vehicle. It must have a 12-volt battery
with a negative ground system.
Caution
If the other vehicle does not have
a 12-volt system with a negative
ground, both vehicles can be
damaged. Only use a vehicle that
has a 12-volt system with a
negative ground for jump starting.
2. Position the two vehicles so that they are not touching.
3. Set the parking brake. See Shifting Into Park 0192.
Caution
If any accessories are left on or
plugged in during the jump
starting procedure, they could be
damaged. The repairs would not
be covered by the vehicle
warranty. Whenever possible, turn
off or unplug all accessories on
either vehicle when jump starting. 4. Turn the ignition off. Turn off all
lights and accessories in both
vehicles, except the hazard
warning flashers if needed.
{Warning
An electric fan can start up even
when the engine is not running
and can injure you. Keep hands,
clothing, and tools away from any
underhood electric fan.
{Warning
Using a match near a battery can
cause battery gas to explode.
People have been hurt doing this,
and some have been blinded.
Use a flashlight if you need more
light.
Battery fluid contains acid that
can burn you. Do not get it on
you. If you accidentally get it in
your eyes or on your skin, flush
the place with water and get
medical help immediately.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-10664916) - 2018 - crc - 9/15/17
Service and Maintenance 359
.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 0361 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

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-10664916) - 2018 - crc - 9/15/17
Index 395
IndexA
About Driving the Vehicle . . . . . . . . . 2
Accessories andModifications . . . . . . . . . . . . . . . . . . 261
Accessory Power . . . . . . . . . . . . . . . 192
Add-On Electrical Equipment . . . 257
Additional Information
OnStar . . . . . . . . . . . . . . . . . . . . . . . 389
Additional Maintenance and Care . . . . . . . . . . . . . . . . . . . . . . 358
Adjustments Lumbar, Front Seats . . . . . . . . . . . . 59
Air Cleaner/Filter, Engine . . . . . . . 274
Air Conditioning . . . . . . . . . . . 160, 162
Air Filter, Passenger Compartment . . . . . . . . . . . . . . . . . 165
Air Vents . . . . . . . . . . . . . . . . . . . . . . . 165
Airbag System Check . . . . . . . . . . . . . . . . . . . . . . . . . . 87
How Does an Airbag
Restrain? . . . . . . . . . . . . . . . . . . . . . 80
Passenger Sensing System . . . . 82
What Makes an Airbag Inflate? . . . . . . . . . . . . . . . . . . . . . . . . 80
What Will You See after an Airbag Inflates? . . . . . . . . . . . . . . . 81
When Should an Airbag Inflate? . . . . . . . . . . . . . . . . . . . . . . . . 79 Airbag System (cont'd)
Where Are the Airbags? . . . . . . . . 78
Airbags Adding Equipment to the
Vehicle . . . . . . . . . . . . . . . . . . . . . . . . 86
Passenger Status Indicator . . . 126
Readiness Light . . . . . . . . . . . . . . 126
Servicing Airbag-Equipped Vehicles . . . . . . . . . . . . . . . . . . . . . . . 86
System Check . . . . . . . . . . . . . . . . . . 76
Alarm Vehicle Security . . . . . . . . . . . . . . . . 46
Alert Lane Change . . . . . . . . . . . . . . . . . 232
Side Blind Zone (SBZA) . . . . . . 232
All-Season Tires . . . . . . . . . . . . . . . . 301
All-Wheel Drive . . . . . . . . . . . . 209, 285
Antilock Brake System (ABS) . . . 210 Warning Light . . . . . . . . . . . . . . . . . 131
Appearance Care Exterior . . . . . . . . . . . . . . . . . . . . . . . 341
Interior . . . . . . . . . . . . . . . . . . . . . . . . 346
Assistance Program,
Roadside . . . . . . . . . . . . . . . . . . . . . . 373
Assistance Systems for Driving . . . . . . . . . . . . . . . . . . . . . . . . 228
Assistance Systems for Parking and Backing . . . . . . . . . . 223