2021 GMC TERRAIN service

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
Mexico-14420055) - 2021 - CRC - 11/13/20
Driving and Operating 201
engine will not start in Service Mode. Press
ENGINE START/STOP again to turn the
vehicle off.
Starting the Engine
Shift the vehicle into P (Park) or N (Neutral).
To restart the engine when the vehicle is
already moving, use N (Neutral) only.
Caution
Do not try to shift to P (Park) if the
vehicle is moving. If you do, you could
damage the transmission. Shift to P (Park)
only when the vehicle is stopped.
Caution
If you add electrical parts or accessories,
you could change the way the engine
operates. Any resulting damage would
not be covered by the vehicle warranty.
SeeAdd-On Electrical Equipment 0256.
1. With the Keyless Access system, the Remote Keyless Entry (RKE) transmitter
must be in the vehicle. Press ENGINE
START/STOP with the brake pedal
applied. When the engine begins
cranking, let go of the button. The idle speed will go down as the
engine gets warm. Do not race the
engine immediately after starting it.
If the RKE transmitter is not in the
vehicle, if there is interference, or if the
RKE battery is low, a Driver Information
Center (DIC) will display a message. See
Remote Keyless Entry (RKE) System
Operation
07.
Caution
Cranking the engine for long periods of
time, by trying to start the engine
immediately after cranking has ended,
can overheat and damage the cranking
motor, and drain the battery. Wait at
least 15 seconds between each try, to let
the cranking motor cool down.
2. If the engine does not start after five to 10 seconds, especially in very cold
weather (below −18 °C or 0 °F), it could
be flooded with too much gasoline. Try
pushing the accelerator pedal all the way
to the floor and holding it there as you
press ENGINE START/STOP. Wait at least
15 seconds between each try, to allow
the cranking motor to cool down. When
the engine starts, release the accelerator. If the vehicle starts briefly but then
stops again, do the same thing. This
clears the extra gasoline from the
engine. Do not race the engine
immediately after starting it. Operate
the engine and transmission gently until
the oil warms up and lubricates all
moving parts.
Stop/Start System
This vehicle has a Stop/Start system to shut
off the engine to help conserve fuel. It has
components designed for the increased
number of starts.
{Warning
The automatic engine Stop/Start feature
causes the engine to shut off while the
vehicle is still on. Do not exit the vehicle
before shifting to P (Park). The vehicle
may restart and move unexpectedly.
Always shift to P (Park), and then turn
the ignition off before exiting the vehicle.
Auto Engine Stop/Start
When the brakes are applied and the vehicle
is at a complete stop, the engine may turn
off. When stopped, the tachometer displays
AUTO STOP. See Tachometer090. When

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
206 Driving and Operating
Caution
The manual park release is not intended
to be used for towing. Damage may
result from using the manual park release
in this way. The repairs would not be
covered by the vehicle warranty.
Pulling the manual park release while the
vehicle is on, or turning the ignition on
while the manual park release is pulled, will
result in a Service Transmission message
being displayed.
To place the vehicle in N (Neutral) using the
manual park release: 1. Ensure the vehicle is on level ground and set the parking brake. Release the brake
pedal.
2. Turn the vehicle off.
3. Use a flat-bladed tool to remove the interior trim panel on the center console
to the right of the accelerator pedal.
4. Ensure more than one minute has elapsed since Step 2. Apply the brake
pedal.5. Pull the manual park release lever 90° toits latching position.
6. With the brake pedal released, place the ignition in ACC/ACCESSORY. Then apply
the brake pedal and release the parking
brake.
7. Ensure there are no loose objects in the area that could bump the manual park
release lever.
To return the vehicle to P (Park) using the
manual park release: 1. Bring the vehicle to a complete stop.

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
Mexico-14420055) - 2021 - CRC - 11/13/20
Driving and Operating 213
cannot be applied or released. To prevent
draining the battery, avoid unnecessary
repeated cycles of the EPB.
The system has a red parking brake status
light and an amber service parking brake
warning light. SeeElectric Parking Brake
Light 095 and
Service Electric Parking Brake Light 095.
There are also parking brake-related Driver
Information Center (DIC) messages.
Before leaving the vehicle, check the red
parking brake status light to ensure that the
parking brake is applied.
EPB Apply
To apply the EPB:
1. Be sure the vehicle is at a complete stop.
2. Press the EPB switch momentarily.
The red parking brake status light will flash
and then stay on once the EPB is fully
applied. If the red parking brake status light
flashes continuously, then the EPB is only
partially applied or there is a problem with
the EPB. A DIC message will display. Release
the EPB and try to apply it again. If the
light does not come on, or keeps flashing, have the vehicle serviced. Do not drive the
vehicle if the red parking brake status light
is flashing. See your dealer.
If the amber service parking brake warning
light is on, press the EPB switch. Continue to
hold the switch until the red parking brake
status light remains on. If the amber service
parking brake warning light is on, see your
dealer.
If the EPB is applied while the vehicle is
moving, the vehicle will decelerate as long
as the switch is pressed. If the switch is
pressed until the vehicle comes to a stop,
the EPB will remain applied.
The vehicle may automatically apply the EPB
in some situations when the vehicle is not
moving. This is normal, and is done to
periodically check the correct operation of
the EPB system, or at the request of other
safety functions that utilize the EPB.
If the EPB fails to apply, block the rear
wheels to prevent vehicle movement.
EPB Release
To release the EPB:
1. Turn the ignition on or to ACC/ ACCESSORY.
2. Apply and hold the brake pedal. 3. Press the EPB switch momentarily.
The EPB is released when the red parking
brake status light is off.
If the amber service parking brake warning
light is on, release the EPB by pressing and
holding the EPB switch. Continue to hold the
switch until the red parking brake status
light is off. If either light stays on after
release is attempted, see your dealer.
Caution
Driving with the parking brake on can
overheat the brake system and cause
premature wear or damage to brake
system parts. Make sure that the parking
brake is fully released and the brake
warning light is off before driving.
If you are towing a trailer and parking on a
hill, see Driving Characteristics and Towing
Tips 0249.
Automatic EPB Release
The EPB will automatically release if the
vehicle is running, placed into gear, and an
attempt is made to drive away. Avoid rapid
acceleration when the EPB is applied, to
preserve parking brake lining life.

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 237
After completely passing a large enough
space, an audible beep occurs and a red stop
symbol is displayed.
If the vehicle is in R (Reverse), but does not
steer into the expected space, this may be
because the system is maneuvering the
vehicle into a previously detected space. The
APA system does not need service.
APA will instruct the vehicle to stop once a
large enough space is found. Follow the
displayed instructions. When instructed todrive in reverse, shift to R (Reverse) to
engage automatic steering. The steering
wheel will briefly vibrate as a reminder to
remove hands from the steering wheel.
Check surroundings and continue braking or
accelerating as needed, and be prepared to
stop to avoid vehicles, pedestrians,
or objects.
If the vehicle exceeds 10 km/h (6 mph), APA
is automatically disengaged and automatic
steering will turn off. A progress arrow
displays the status of the parking maneuver.
Depending on the space size, additional
maneuvers may be required, and there will
be additional instructions. When changing
gears, allow the automatic steering to
complete before continuing the parking
maneuver. Upon successful completion of a
maneuver, APA will beep and display a
PARKING COMPLETE message. Place the
vehicle in P (Park).
APA may automatically disengage if:
.The steering wheel is used by the driver.
.The maximum allowed speed is exceeded.
.There is a failure with the APA system.
.Electronic stability control or antilock
brakes are activated.
.A high priority vehicle message is
displayed in the Driver Information
Center (DIC).
To cancel APA, press
Oagain.
When the System Does Not Seem to Work
Properly
The APA system may require a short period
of driving along curves to calibrate.
Assistance Systems for Driving
If equipped, when driving the vehicle in a
forward gear, Forward Collision Alert (FCA),
Lane Keep Assist (LKA), Side Blind Zone Alert
(SBZA), Lane Change Alert (LCA), Automatic
Emergency Braking (AEB), and/or the Front
Pedestrian Braking (FPB) System can help to
avoid a crash or reduce crash damage.
Forward Collision Alert (FCA)
System
If equipped, the FCA system may help to
avoid or reduce the harm caused by
front-end crashes. When approaching a
vehicle ahead too quickly, FCA provides a
red flashing alert on the windshield and
rapidly beeps or pulses the driver seat. FCA
also lights an amber visual alert if following
another vehicle much too closely.

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
240 Driving and Operating
Warning (Continued)
vehicle. AEB will not brake outside of its
operating speed range and only responds
to detected vehicles.
AEB may not:
.Detect a vehicle ahead on winding or
hilly roads.
.Detect all vehicles, especially vehicles
with a trailer, tractors, muddy
vehicles, etc.
.Detect a vehicle when weather limits
visibility, such as in fog, rain, or snow.
.Detect a vehicle ahead if it is partially
blocked by pedestrians or other
objects.
Complete attention is always required
while driving, and you should be ready to
take action and apply the brakes and/or
steer the vehicle to avoid crashes.
AEB may slow the vehicle to a complete
stop to try to avoid a potential crash. If this
happens, AEB may engage the Electric
Parking Brake (EPB) to hold the vehicle at a
stop. Release the EPB or firmly press the
accelerator pedal.
{Warning
AEB may automatically brake the vehicle
suddenly in situations where it is
unexpected and undesired. It could
respond to a turning vehicle ahead,
guardrails, signs, and other non-moving
objects. To override AEB, firmly press the
accelerator pedal, if it is safe to do so.
Intelligent Brake Assist (IBA)
IBA may activate when the brake pedal is
applied quickly by providing a boost to
braking based on the speed of approach and
distance to a vehicle ahead.
Minor brake pedal pulsations or pedal
movement during this time is normal and
the brake pedal should continue to be
applied as needed. IBA will automatically
disengage only when the brake pedal is
released.
{Warning
IBA may increase vehicle braking in
situations when it may not be necessary.
You could block the flow of traffic. If this
occurs, take your foot off the brake pedal
and then apply the brakes as needed. AEB and IBA can be disabled through vehicle
personalization. See
“Collision/Detection
Systems” underVehicle Personalization
0 108.
{Warning
Using AEB or IBA while towing a trailer
could cause you to lose control of the
vehicle and crash. Turn the system to
Alert or Off when towing a trailer.
A system unavailable message may
display if:
.The front of the vehicle or windshield is
not clean.
.Heavy rain or snow is interfering with
object detection.
.There is a problem with the StabiliTrak/
Electronic Stability Control (ESC) system.
The AEB system does not need service.
Front Pedestrian Braking (FPB)
System
If equipped, the Front Pedestrian Braking
(FPB) system may help avoid or reduce the
harm caused by front-end crashes with
nearby pedestrians when driving in a
forward gear. FPB displays an amber