service indicator GMC TERRAIN 2021 User Guide

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
Mexico-14420055) - 2021 - CRC - 11/13/20
Instruments and Controls 99
This light should come on briefly as the
engine is started. If it does not come on,
have the vehicle serviced by your dealer.
If the light comes on and stays on, it means
that oil is not flowing through the engine
properly. The vehicle could be low on oil
and might have some other system
problem. See your dealer.
Low Fuel Warning Light
Base Level English Shown, Metric Similar
Uplevel
A Low Fuel Warning Light near the fuel
gauge comes on briefly when the ignition is
turned on as a check to show it is working.
It also comes on when the fuel gauge
indicator nears empty. The light turns off
when fuel is added. If it does not, have the
vehicle serviced.
Security Light
The security light should come on briefly as
the engine is started. If it does not come on,
have the vehicle serviced by your dealer.
If the system is working normally, the
indicator light turns off. If the light stays on and the engine does
not start, there could be a problem with the
theft-deterrent system. See
Immobilizer
Operation 023.
High-Beam On Light
This light comes on when the high-beam
headlamps are in use. See Headlamp High/
Low-Beam Changer 0117.
IntelliBeam Light
This light comes on when the IntelliBeam
system, if equipped, is enabled. See Exterior
Lamp Controls 0116.

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
Mexico-14420055) - 2021 - CRC - 11/13/20
178 Climate Controls
Climate Controls
Climate Control Systems
Climate Control Systems . . . . . . . . . . . . . . . 178
Dual Automatic Climate ControlSystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180
Air Vents
Air Vents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182
Maintenance
Passenger Compartment Air Filter . . . . . 182
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183
Climate Control Systems
With this system the heating, cooling, and ventilation in the vehicle can be controlled.
1. Fan Control
2. A/C (Air Conditioning)
3. Air Delivery Mode Controls
4. Defrost
5. TEMP (Temperature Control)
6. Rear Window Defogger
7. Air Recirculation
9:Turn clockwise or counterclockwise to
increase or decrease the fan speed or turn
the fan off. TEMP :
Turn the knob clockwise or
counterclockwise to increase or decrease the
temperature.
Air Delivery Mode Control : Press
Y,\,
[, or-to change the direction of the
airflow. An indicator light comes on in the
selected mode button.
Y: Air is directed to the instrument panel
outlets.
\: Air is divided between the instrument
panel and floor outlets.

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
Mexico-14420055) - 2021 - CRC - 11/13/20
200 Driving and Operating
Information Center (DIC). When the vehicle
is shifted into P (Park), the ignition system
will turn off.
The vehicle may have an electric steering
column lock. The lock is activated when the
vehicle is turned off and either front door is
opened. A sound may be heard as the lock
actuates or releases. The steering column
lock may not release with the wheels turned
off center. If this happens, the vehicle may
not start. Move the steering wheel from left
to right while attempting to start the
vehicle. If this does not work, the vehicle
needs service.
Do not turn the engine off when the vehicle
is moving. This will cause a loss of power
assist in the brake and steering systems and
disable the airbags.
If the vehicle must be turned off in an
emergency:1. Brake using a firm and steady pressure. Do not pump the brakes repeatedly. This
may deplete power assist, requiring
increased brake pedal force. 2. Shift the vehicle to N (Neutral). This can
be done while the vehicle is moving.
After shifting to N (Neutral), firmly apply
the brakes and steer the vehicle to a
safe location.
3. Come to a complete stop and shift to P (Park).
4. Set the parking brake. See Electric
Parking Brake 0212. Press ENGINE
START/STOP to turn the vehicle off.
{Warning
Turning off the vehicle while moving may
cause loss of power assist in the brake
and steering systems and disable the
airbags. While driving, only shut the
vehicle off in an emergency.
If the vehicle cannot be pulled over and
must be shut off while driving, press and
hold ENGINE START/STOP for longer than
two seconds, or press twice in five seconds.
ACC/ACCESSORY (Amber Indicator Light) :
This mode allows you to use some electrical
accessories when the engine is off. With the ignition off, pressing the button
one time without the brake pedal applied
will place the ignition system in ACC/
ACCESSORY.
The ignition will switch from ACC/
ACCESSORY to OFF after five minutes to
prevent battery rundown.
ON/RUN/START (Green Indicator Light) :
This
mode is for starting and driving. With the
ignition off and the brake pedal applied,
pressing the button once will turn the
ignition on. Once engine cranking begins,
release the button. Engine cranking will
continue until the engine starts. See Starting
the Engine 0201. The ignition will then
remain in on.
Service Mode
This power mode is available for service and
diagnostics, and to verify the proper
operation of the malfunction indicator lamp
as may be required for emission inspection
purposes. With the vehicle off and the brake
pedal not applied, pressing and holding
ENGINE START/STOP for more than
five seconds will place the vehicle in Service
Mode. The instruments and audio systems
will operate as they do in ON/RUN, but the
vehicle will not be able to be driven. The

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
Mexico-14420055) - 2021 - CRC - 11/13/20
Driving and Operating 205
Leaving the Vehicle with the Engine
Running
{Warning
It can be dangerous to leave the vehicle
with the engine running. It could
overheat and catch fire.
It is dangerous to get out of the vehicle
if the vehicle is not in P (Park) with the
parking brake set. The vehicle can roll.
Do not leave the vehicle when the engine
is running. If you have left the engine
running, the vehicle can move suddenly.
You or others could be injured. To be
sure the vehicle will not move, even
when you are on fairly level ground,
always set the parking brake and shift
the vehicle to P (Park). SeeShifting Into
Park 0204. If you are towing a trailer,
see Driving Characteristics and Towing
Tips 0249.
If you have to leave the vehicle with the
engine running, the vehicle must be in
P (Park) with the parking brake set.
Confirm that the vehicle is in P (Park).
Torque Lock
Torque lock is when the weight of the
vehicle puts too much force on the parking
pawl in the transmission. This happens when
parking on a hill and shifting the
transmission into P (Park) is not done
properly and then it is difficult to shift out
of P (Park). To prevent torque lock, set the
parking brake and then shift into P (Park). To
find out how, see “Shifting Into Park” listed
previously.
On certain steep grades, the transmission
will automatically set the parking brake to
prevent torque lock.
If torque lock does occur, the vehicle may
need to be pushed uphill by another vehicle
to relieve the parking pawl pressure, so you
can shift out of P (Park).
Shifting out of Park
This vehicle is equipped with an electronic
transmission. If the vehicle has an
uncharged battery or a battery with low
voltage, try charging or jump starting the
battery. See Jump Starting - North America
0 316. To shift out of P (Park):
1. Ensure the engine is running.
2. Apply the brake pedal.
3. Press or pull the desired shift switch on the center stack.
4. The P indicator will turn white and the gear indicator will turn red when the
vehicle is no longer in P (Park).
If the vehicle cannot shift out of P (Park), a
Driver Information Center (DIC) message will
be displayed. See your dealer for service.
Manual Park Release
Vehicles with a gasoline engine may include
a manual park release that can be used to
shift the vehicle into N (Neutral) when the
engine is not running.
{Warning
The transmission will be placed in
N (Neutral) when the manual park release
is pulled. The vehicle can roll and you or
others could be injured. Ensure the
vehicle is on level ground.

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
Mexico-14420055) - 2021 - CRC - 11/13/20
Driving and Operating 229
{Warning
On curves, ACC may respond to a vehicle
in another lane, or may not have time to
react to a vehicle in your lane. You could
crash into a vehicle ahead of you, or lose
control of your vehicle. Give extra
attention in curves and be ready to use
the brakes if necessary. Select an
appropriate speed while driving in curves.
ACC may operate differently in a sharp
curve. It may reduce the vehicle speed if the
curve is too sharp.
ACC automatically slows the vehicle down
while navigating the curve and may increase
speed out of the curve, but will not exceed
the set speed.
When following a vehicle and entering a
curve, ACC may not detect the vehicle ahead
and accelerate to the set speed. When this
happens, the vehicle ahead indicator will not
appear.
ACC may detect a vehicle that is not in your
lane and apply the brakes.
ACC may occasionally provide an alert and/
or braking that is considered unnecessary.
It could respond to vehicles in different
lanes or stationary objects when entering or
exiting a curve. This is normal operation.
The vehicle does not need service. Other Vehicle Lane Changes
ACC will not detect a vehicle ahead until it
is completely in the lane. The brakes may
need to be manually applied.
Objects Not Directly in Front of Your Vehicle
The detection of objects in front of the
vehicle may not be possible if:
.The vehicle or object ahead is not within
your lane.
.The vehicle ahead is shifted, not centered,
or is shifted to one side of the lane.
Driving in Narrow Lanes
Vehicles in adjacent traffic lanes or roadside
objects may be incorrectly detected when
located along the roadway.

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
Mexico-14420055) - 2021 - CRC - 11/13/20
Driving and Operating 239
Tailgating Alert
The vehicle ahead indicator will display
amber when you are following a vehicle
ahead much too closely.
Selecting the Alert Timing
The Collision Alert control is on the steering
wheel. Press
[to set the FCA timing to
Far, Medium, or Near, or on some vehicles,
Off. The first button press shows the current
setting on the DIC. Additional button presses
will change this setting. The chosen setting
will remain until it is changed and will affect
the timing of both the Collision Alert and
the Tailgating Alert features. The timing of
both alerts will vary based on vehicle speed.
The faster the vehicle speed, the farther
away the alert will occur. Consider traffic
and weather conditions when selecting the
alert timing. The range of selectable alert
timings may not be appropriate for all
drivers and driving conditions.
Following Distance Indicator
The following distance to a moving vehicle
ahead in your path is indicated in following
time in seconds on the Driver Information
Center (DIC). See Driver Information Center
(DIC) (Base and Midlevel) 0100 or
Driver Information Center (DIC) (Uplevel)
0 105. The minimum following time is
0.5 seconds away. If there is no vehicle
detected ahead, or the vehicle ahead is out
of sensor range, dashes will be displayed.
Unnecessary Alerts
FCA may provide unnecessary alerts for
turning vehicles, vehicles in other lanes,
objects that are not vehicles, or shadows.
These alerts are normal operation and the
vehicle does not need service.
Cleaning the System
If the FCA system does not seem to operate
properly, this may correct the issue:
.Clean the outside of the windshield in
front of the rearview mirror.
.Clean the entire front of the vehicle.
.Clean the headlamps.
Automatic Emergency
Braking (AEB)
If the vehicle has Forward Collision Alert
(FCA), it also has AEB, which includes
Intelligent Brake Assist (IBA). When the
system detects a vehicle ahead in your path
that is traveling in the same direction that
you may be about to crash into, it can
provide a boost to braking or automatically
brake the vehicle. This can help avoid or
lessen the severity of crashes when driving
in a forward gear. Depending on the
situation, the vehicle may automatically
brake moderately or hard. This automatic
emergency braking can only occur if a
vehicle is detected. This is shown by the FCA
vehicle ahead indicator being lit. See
Forward Collision Alert (FCA) System 0237.
The system works when driving in a forward
gear between 8 km/h (5 mph) and 80 km/h
(50 mph). It can detect vehicles up to
approximately 60 m (197 ft).
{Warning
AEB is an emergency crash preparation
feature and is not designed to avoid
crashes. Do not rely on AEB to brake the (Continued)

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
Mexico-14420055) - 2021 - CRC - 11/13/20
Driving and Operating 245
Warning (Continued)
Always keep your attention on the road
and maintain proper vehicle position
within the lane, or vehicle damage,
injury, or death could occur. Always keep
the windshield, headlamps, and camera
sensors clean and in good repair. Do not
use LKA in bad weather conditions or on
roads with unclear lane markings, such as
construction zones.
{Warning
Using LKA while towing a trailer or on
slippery roads could cause loss of control
of the vehicle and a crash. Turn the
system off.
How the System Works
LKA uses a camera sensor installed on the
windshield ahead of the rearview mirror to
detect lane markings. It may provide brief
steering assist if it detects an unintended
lane departure. It may further provide an
audible alert or the driver seat may pulse
indicating that a lane marking has been
crossed.To turn LKA on and off, press
Aon the
center console. If equipped, the indicator
light on the button comes on when LKA is
on and turns off when LKA is disabled.
When on,
Ais white, if equipped,
indicating that the system is not ready to
assist.
Ais green if LKA is ready to
assist. LKA may assist by gently turning the
steering wheel if the vehicle approaches a
detected lane marking.
Ais amber when
assisting. It may also provide a Lane
Departure Warning (LDW) alert by flashing
Aamber if the vehicle crosses a
detected lane marking. Additionally, there
may be three beeps, or the driver seat may
pulse three times, on the right or left,
depending on the lane departure direction.
Take Steering
The LKA system does not continuously steer
the vehicle. If LKA does not detect active
driver steering, an alert and chime may be
provided. Steer the vehicle to dismiss. LKA
may become temporarily unavailable after
repeated take steering alerts.
When the System Does Not Seem to
Work Properly
The system performance may be
affected by:
.Close vehicles ahead.
.Sudden lighting changes, such as when
driving through tunnels.
.Banked roads.
.Roads with poor lane markings, such as
two-lane roads.
If the LKA system is not functioning
properly when lane markings are clearly
visible, cleaning the windshield may help.
A camera blocked message may display if
the camera is blocked. Some driver
assistance systems may have reduced
performance or not work at all. An LKA or
LDW unavailable message may display if the
systems are temporarily unavailable. This
message could be due to a blocked camera.
The LKA system does not need service. Clean
the outside of the windshield behind the
rearview mirror.
LKA assistance and/or LDW alerts may occur
due to tar marks, shadows, cracks in the
road, temporary or construction lane
markings, or other road imperfections. This

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
Mexico-14420055) - 2021 - CRC - 11/13/20
256 Driving and Operating
Conversions and Add-Ons
Add-On Electrical Equipment
{Warning
The Data Link Connector (DLC) is used for
vehicle service and Emission Inspection/
Maintenance testing. SeeMalfunction
Indicator Lamp (Check Engine Light) 093.
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.
Caution
Some electrical equipment can damage
the vehicle or cause components to not
work and would not be covered by the
vehicle warranty. Always check with your
dealer before adding electrical equipment.
Add-on equipment can drain the vehicle's
12-volt battery, even if the vehicle is not
operating. The vehicle has an airbag system. Before
attempting to add anything electrical to the
vehicle, see
Servicing the Airbag-Equipped
Vehicle 055 and
Adding Equipment to the Airbag-Equipped
Vehicle 056.

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
Mexico-14420055) - 2021 - CRC - 11/13/20
Service and Maintenance 337
.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 0339 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-14420055) - 2021 - CRC - 11/13/20
Index 369
Fuel (cont'd)Economy, Driving for Better . . . . . . . . . . . 187
Filling a Portable Fuel Container . . . . . . . 248
Filling the Tank . . . . . . . . . . . . . . . . . . . . . . . . 247
Foreign Countries . . . . . . . . . . . . . . . . . . . . . . 246
Gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Low Fuel Warning Light . . . . . . . . . . . . . . . . 99
Prohibited Fuels . . . . . . . . . . . . . . . . . . . . . . . 246
Recommended . . . . . . . . . . . . . . . . . . . . . . . . . 246
Top Tier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246
Fuses Engine Compartment Fuse Block . . . . . . . 281
Fuses and Circuit Breakers . . . . . . . . . . . . . 280
Instrument Panel Fuse Block . . . . . . . . . . . 284
Rear Compartment Fuse Block . . . . . . . . . 285
G
Garage Door Opener . . . . . . . . . . . . . . . . . . . . . . 112
Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276
Gauges Engine Coolant Temperature . . . . . . . . . . . . 91
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Odometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Speedometer . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Tachometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Trip Odometer . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Warning Lights and Indicators . . . . . . . . . . 84 General Information
Service and Maintenance . . . . . . . . . . . . . . 330
Towing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
Vehicle Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 258
Global Positioning System (GPS) . . . . . . . . . 148
Glove Box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
GM Mobility Reimbursement Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 349
Guidance Problems with the Route . . . . . . . . . . . . . . 149
H
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . . . 277
Hazard Warning Flashers . . . . . . . . . . . . . . . . . 119
HD Radio Technology . . . . . . . . . . . . . . . . . . . . . 132
Head Restraints . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
HeadlampsAiming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277
Automatic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . . 277
Daytime Running Lamps (DRL) . . . . . . . . . . 118
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
High Intensity Discharge (HID)Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277
High-Beam On Light . . . . . . . . . . . . . . . . . . . . 99
High/Low Beam Changer . . . . . . . . . . . . . . . 117
Lamps On Reminder . . . . . . . . . . . . . . . . . . . 100 Heated
Rear Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Steering Wheel . . . . . . . . . . . . . . . . . . . . . . . . . 79
Heated and Ventilated Front Seats . . . . . . . .35
Heated Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Heater Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203
Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178, 180
High-Beam On Light . . . . . . . . . . . . . . . . . . . . . . 99
Hill and Mountain Roads . . . . . . . . . . . . . . . . 194
Hill Descent Control (HDC) . . . . . . . . . . . . . . . . 217
Hill Descent Control Light . . . . . . . . . . . . . . . . . 96
Hill Start Assist (HSA) . . . . . . . . . . . . . . . . . . . . .214
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
How to Wear Seat Belts Properly . . . . . . . . . .41
HVAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178, 180
I
If the System Needs Service . . . . . . . . . . . . . 149
Ignition Positions . . . . . . . . . . . . . . . . . . . . . . . . 199
Immobilizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Indicator Pedestrian Ahead . . . . . . . . . . . . . . . . . . . . . . . 97
Vehicle Ahead . . . . . . . . . . . . . . . . . . . . . . . . . . 97
Infants and Young Children, Restraints . . . . 58
Information
Publication Ordering . . . . . . . . . . . . . . . . . . . 353