
GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
238 Driving and Operating
ACC Automatically Disengages
ACC may automatically disengage
and the driver will need to manually
apply the brakes to slow the
vehicle if:
.The front camera is blocked or
visibility is reduced.
. The Traction Control System
(TCS) or StabiliTrak/ESC system
has activated or been disabled.
. There is a fault in the system.
. A DIC message displays to
indicate that ACC is temporarily
unavailable. The ACC indicator will turn white
when ACC is no longer active.
In some cases, when ACC is
temporarily unavailable, regular
cruise control may be used. See
“Switching Between ACC and
Regular Cruise Control”
in this
section. Always consider driving
conditions before using either cruise
control system.
Notification to Resume ACC
ACC will maintain a follow gap
behind a detected vehicle and slow
your vehicle to a stop behind that
vehicle.
If the stopped vehicle ahead has
driven away and ACC has not
resumed, the vehicle ahead
indicator will flash as a reminder to
check traffic ahead before
proceeding. In addition, the left and
right sides of the Safety Alert Seat
will pulse three times, or three
beeps will sound. See ”Alert Type”
and “Adaptive Cruise Go Notifier” in
“Collision/Detection Systems” under
Vehicle Personalization 0152. When the vehicle ahead drives
away, press RES+ or the
accelerator pedal to resume ACC.
If stopped for more than
two minutes or if the driver door is
opened and the driver seat belt is
unbuckled, the ACC automatically
applies the Electric Parking Brake
(EPB) to hold the vehicle. The EPB
status light will turn on. See
Electric
Parking Brake 0219.
A DIC warning message may
display indicating to shift to P (Park)
before exiting the vehicle. See
Vehicle Messages 0151.
{Warning
If ACC has stopped the vehicle,
and if ACC is disengaged, turned
off, or canceled, the vehicle will
no longer be held at a stop. The
vehicle can move. When ACC is
holding the vehicle at a stop,
always be prepared to manually
apply the brakes.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
Driving and Operating 239
{Warning
Leaving the vehicle without
placing it in P (Park) can be
dangerous. Do not leave the
vehicle while it is being held at a
stop by ACC. Always place the
vehicle in P (Park) and turn off
the ignition before leaving the
vehicle.
ACC Override
If using the accelerator pedal while
ACC is active, the ACC indicator
turns blue on the instrument cluster
indicating ACC braking will not
occur. ACC will resume operation
when the accelerator pedal is not
being pressed.
{Warning
The ACC will not automatically
apply the brakes if your foot is
resting on the accelerator pedal.
You could crash into a vehicle
ahead of you. Curves in the Road
{Warning
On curves, ACC may not detect a
vehicle ahead in your lane. You
could be startled if the vehicle
accelerates up to the set speed,
especially when following a
vehicle exiting or entering exit
ramps. You could lose control of
the vehicle or crash. Do not use
ACC while driving on an entrance
or exit ramp. Always be ready to
use the brakes if necessary.
{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
(Continued)
Warning (Continued)
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.
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.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
240 Driving and Operating
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.
Do Not Use ACC on Hills and
When Towing a Trailer
Do not use ACC when driving on
steep hills or when towing a trailer.
ACC will not detect a vehicle in the
lane while driving on steep hills.
If the brakes are applied, ACC
disengages.
Disengaging ACC
There are three ways to
disengage ACC:
.
Step lightly on the brake pedal.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
Driving and Operating 243
Warning (Continued)
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.
Audible or Safety Alert Seat
Some driver assistance features
alert the driver of obstacles by
beeping. To change the volume of
the warning chime, see “Comfort
and Convenience” underVehicle
Personalization 0152.
If equipped with the Safety Alert
Seat, the driver seat cushion may
provide a vibrating pulse alert
instead of beeping. To change this,
see “Collision/Detection Systems”
under Vehicle Personalization
0 152.
Cleaning
Depending on vehicle options, keep
these areas of the vehicle clean to
ensure the best driver assistance
feature performance. Driver Information Center (DIC) messages
may display when the systems are
unavailable or blocked.
.
Front and rear bumpers and the
area below the bumpers
. Front grille and headlamps
. Front camera lens in the front
grille or near the front emblem
. Front side and rear side panels
. Outside of the windshield in front
of the rearview mirror
. Side camera lens on the bottom
of the outside mirrors
. Rear side corner bumpers
. Rear Vision Camera above the
license plate
Assistance Systems for
Parking or Backing
If equipped, the Rear Vision Camera
(RVC), Rear Park Assist (RPA),
Front Park Assist (FPA), Surround
Vision, Rear Cross Traffic Alert
(RCTA), and Automatic Parking
Assist (APA) may help the driver
park or avoid objects. Always check
around the vehicle when parking or
backing.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
248 Driving and Operating
Automatic Parking
Assist (APA)
If equipped, APA searches for and
steers the vehicle into parallel and
perpendicular parking spots. When
using APA, you must still shift gears,
and control the brakes and
accelerator. A display and audible
beeps help to guide parking
maneuvers.
{Warning
APA does not apply the brakes.
APA may not detect objects in the
parking space, objects that are
soft or narrow, objects high off the
ground such as flatbed trucks,
or objects below ground level
such as large potholes. Always
verify that the parking space is
appropriate for parking a vehicle.
APA does not respond to changes
in the parking space, such as
movement of an adjacent vehicle,
or a person or object entering the
parking space. APA does not(Continued)
Warning (Continued)
detect or avoid traffic that is
behind or alongside of the
vehicle. Always be prepared to
stop the vehicle during the
parking maneuver.
Press
Oon the center console to
enable the system to search for a
parking space that is large enough
and within 1.5 m (5 ft) of the vehicle.
The vehicle speed must be below
30 km/h (18 mph). The system
cannot:
. Detect whether it is a legal
parking space.
. Park exactly lined up with the
vehicle next to it if the spot is
approached at an angle or if the
parking space is angled.
. Park exactly centered in a spot
that is marked too large.
. Always detect short curbs. When enabled, APA searches for
parallel parking spaces to the right
of the vehicle. To search for a
parking space to the left, turn on the
left turn signal or, if available,
change the side selection in the
infotainment display. To switch the
parking mode between parallel and
perpendicular, press and hold
O
during the search process or,
if available, change the parking
mode in the infotainment display.
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

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
Driving and Operating 249
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 to drive 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
Departure Warning (LDW), Lane
Keep Assist (LKA), Side Blind Zone
Alert (SBZA), Lane Change Alert
(LCA), Forward Automatic Braking
(FAB), and/or the Front Pedestrian
Braking (FPB) System can help to
avoid a crash or reduce crash
damage.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
250 Driving and Operating
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.
FCA detects vehicles within a
distance of approximately 60 m
(197 ft) and operates at speeds
above 8 km/h (5 mph).
{Warning
FCA is a warning system and
does not apply the brakes. When
approaching a slower-moving or
stopped vehicle ahead too rapidly,
or when following a vehicle too
closely, FCA may not provide a
warning with enough time to help(Continued)
Warning (Continued)
avoid a crash. It also may not
provide any warning at all. FCA
does not warn of pedestrians,
animals, signs, guardrails,
bridges, construction barrels,
or other objects. Be ready to take
action and apply the brakes. See
Defensive Driving0181.
FCA can be disabled with the FCA
steering wheel control, or if
equipped, through vehicle
personalization. See “Collision/
Detection Systems” underVehicle
Personalization 0152.
Detecting the Vehicle Ahead
FCA warnings will not occur unless
the FCA system detects a vehicle
ahead. When a vehicle is detected,
the vehicle ahead indicator will
display green. Vehicles may not be
detected on curves, highway exit
ramps, or hills, due to poor visibility;
or if a vehicle ahead is partially
blocked by pedestrians or other
objects. FCA will not detect another
vehicle ahead until it is completely
in the driving lane.
{Warning
FCA does not provide a warning
to help avoid a crash, unless it
detects a vehicle. FCA may not
detect a vehicle ahead if the FCA
sensor is blocked by dirt, snow,
or ice, or if the windshield is
damaged. It may also not detect a
vehicle on winding or hilly roads,
or in conditions that can limit
visibility such as fog, rain,
or snow, or if the headlamps or
windshield are not cleaned or in
(Continued)

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
252 Driving and Operating
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.
Forward Automatic
Braking (FAB)
If the vehicle has Forward Collision
Alert (FCA), it also has FAB, 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 forward automatic
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 0250.
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
FAB is an emergency crash
preparation feature and is not
designed to avoid crashes. Do
not rely on FAB to brake the
vehicle. FAB will not brake
outside of its operating speed
range and only responds to
detected vehicles.
FAB may not: (Continued)
Warning (Continued)
.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.
FAB may slow the vehicle to a
complete stop to try to avoid a
potential crash. If this happens, FAB
may engage the Electric Parking
Brake (EPB) to hold the vehicle at a
stop. Release the EPB or firmly
press the accelerator pedal.