brakes GMC TERRAIN 2021 User Guide

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
Mexico-14420055) - 2021 - CRC - 11/13/20
194 Driving and Operating
Hydroplaning
Hydroplaning is dangerous. Water can build
up under the vehicle's tires so they actually
ride on the water. This can happen if the
road is wet enough and you are going fast
enough. When the vehicle is hydroplaning, it
has little or no contact with the road.
There is no hard and fast rule about
hydroplaning. The best advice is to slow
down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet weather
driving tips include:
.Allow extra following distance.
.Pass with caution.
.Keep windshield wiping equipment in
good shape.
.Keep the windshield washer fluid reservoir
filled.
.Have good tires with proper tread depth.
SeeTires 0287.
.Turn off cruise control.
Hill and Mountain Roads
Driving on steep hills or through mountains
is different than driving on flat or rolling
terrain. Tips include:
.Keep the vehicle serviced and in good
shape.
.Check all fluid levels and brakes, tires,
cooling system, and transmission.
.Shift to a lower gear when going down
steep or long hills.
{Warning
Using the brakes to slow the vehicle on a
long downhill slope can cause brake
overheating, can reduce brake
performance, and could result in a loss of
braking. Shift the transmission to a lower
gear to let the engine assist the brakes
on a steep downhill slope.
{Warning
Coasting downhill in N (Neutral) or with
the ignition off is dangerous. This can
cause overheating of the brakes and loss
of steering assist. Always have the engine
running and the vehicle in gear.
.Drive at speeds that keep the vehicle in
its own lane. Do not swing wide or cross
the center line.
.Be alert on top of hills; something could
be in your lane (e.g., stalled car, crash).
.Pay attention to special road signs (e.g.,
falling rocks area, winding roads, long
grades, passing or no-passing zones) and
take appropriate action.
Winter Driving
Driving on Snow or Ice
Snow or ice between the tires and the road
creates less traction or grip, so drive
carefully. Wet ice can occur at about 0 °C
(32 °F) when freezing rain begins to fall.
Avoid driving on wet ice or in freezing rain
until roads can be treated.
For Slippery Road Driving:
.Accelerate gently. Accelerating too quickly
causes the wheels to spin and makes the
surface under the tires slick.
.Turn on Traction Control. See Traction
Control/Electronic Stability Control 0214.
.The Antilock Brake System (ABS) improves
vehicle stability during hard stops, but
the brakes should be applied sooner than
when on dry pavement. See Antilock
Brake System (ABS) 0212.

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 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/
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Driving and Operating 211
D :This position is for normal driving.
If more power is needed for passing, press
the accelerator pedal down.
To shift into D (Drive):
1. Bring the vehicle to a complete stop.
2. Pull the D (Drive) switch on the center stack.
To shift out of D (Drive): 1. Bring the vehicle to a complete stop.
2. Shift to the desired gear.
Downshifting the transmission in slippery
road conditions could result in skidding. See
“Skidding” underLoss of Control 0190.
Caution
Spinning the tires or holding the vehicle
in one place on a hill using only the
accelerator pedal may damage the
transmission. The repair will not be
covered by the vehicle warranty. If the
vehicle is stuck, do not spin the tires.
When stopping on a hill, use the brakes
to hold the vehicle in place.
Manual Mode
Electronic Range Select (ERS) Mode
ERS or manual mode allows for the selection
of the range of gear positions. Use this
mode when driving downhill or towing a
trailer to limit the top gear and vehicle
speed. The shift position indicator within the
Driver Information Center (DIC) will display a
number next to the L indicating the highest
available gear under manual mode and the
driving conditions when manual mode was
selected.
To use this feature:
1. With the vehicle in D (Drive), press the L (Low) button. 2. Press the plus or minus button on the
center stack to increase or decrease the
gear range available.
When shifting to L (Low), the transmission
will shift to a preset lower gear range. For
this preset range, the highest gear available
is displayed next to the L in the DIC. See
Driver Information Center (DIC) (Base and
Midlevel) 0100 or
Driver Information Center (DIC) (Uplevel)
0 105. All gears below that number are
available to use. For example, when
4 (Fourth) is shown next to the L, 1 (First)
through 4 (Fourth) gears are shifted
automatically. To shift to 5 (Fifth) gear, press
the + (Plus) button or shift into D (Drive).
L (Low) will prevent shifting to a lower gear
range if the engine speed is too high.
If vehicle speed is not reduced within the
time allowed, the lower gear range shift will
not be completed. Slow the vehicle, then
press the −(Minus) button to the desired
lower gear range.
While using ERS, cruise control can be used.
Tow/Haul Mode
For information on the Tow/Haul Mode, see
Driver Mode Control 0218.

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
Mexico-14420055) - 2021 - CRC - 11/13/20
212 Driving and Operating
Automatic Engine Grade Braking
Automatic Engine Grade Braking assists
when driving downhill. It maintains vehicle
speed by automatically implementing a shift
pattern that uses the engine and the
transmission to slow the vehicle. The system
will automatically command downshifts to
reduce vehicle speed. The normal shift
pattern will return once the vehicle is on a
low grade or when the accelerator pedal is
pressed.
While in the Electronic Range Select (ERS)
mode, grade braking is deactivated, allowing
the driver to select a range and limiting the
highest gear available. Grade braking is
available for normal driving and in Tow/
Haul Mode.
SeeAutomatic Transmission 0208.
Drive Systems
All-Wheel Drive
For information on All-Wheel Drive (AWD),
see Driver Mode Control 0218.
Brakes
Antilock Brake System (ABS)
The Antilock Brake System (ABS) helps
prevent a braking skid and maintain steering
while braking hard.
ABS performs a system check when the
vehicle is first driven. A momentary motor
or clicking noise may be heard while this
test is going on, and the brake pedal may
move slightly. This is normal.
If there is a problem with ABS, this warning
light stays on. See Antilock Brake System
(ABS) Warning Light 096.
ABS does not change the time needed to
get a foot on the brake pedal and does not
always decrease stopping distance. If you
get too close to the vehicle ahead, there will
not be enough time to apply the brakes if
that vehicle suddenly slows or stops. Always
leave enough room ahead to stop, even
with ABS.
Using ABS
Do not pump the brakes. Just hold the brake
pedal down firmly. Hearing or feeling ABS
operate is normal.
Braking in Emergencies
ABS allows steering and braking at the same
time. In many emergencies, steering can
help even more than braking.
Electric Parking Brake
The Electric Parking Brake (EPB) can always
be applied, even if the vehicle is off. In case
of insufficient electrical power, the EPB

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
Mexico-14420055) - 2021 - CRC - 11/13/20
214 Driving and Operating
Brake Assist
Brake Assist detects rapid brake pedal
applications due to emergency braking
situations and provides additional braking to
activate the Antilock Brake System (ABS) if
the brake pedal is not pushed hard enough
to activate ABS normally. Minor noise, brake
pedal pulsation, and/or pedal movement
during this time may occur. Continue to
apply the brake pedal as the driving
situation dictates. Brake Assist disengages
when the brake pedal is released.
Hill Start Assist (HSA)
{Warning
Do not rely on the HSA feature. HSA does
not replace the need to pay attention
and drive safely. You may not hear or
feel alerts or warnings provided by this
system. Failure to use proper care when
driving may result in injury, death,
or vehicle damage. SeeDefensive Driving
0 187.
When the vehicle is stopped on a grade, Hill
Start Assist (HSA) prevents the vehicle from
rolling in an unintended direction during the
transition from brake pedal release to accelerator pedal apply. The brakes release
when the accelerator pedal is applied. HSA
brake hold duration may be selectable.
Standard Hold automatically releases the
brakes after a few seconds. Extended Hold
applies the Electric Parking Brake if the
accelerator pedal is not applied within a few
minutes. If hold duration is selectable, see
"Extended Hill Start Assist" in
Vehicle
Personalization 0108. The brakes may also
release under other conditions. Do not rely
on HSA to hold the vehicle.
HSA is available when the vehicle is facing
uphill in a forward gear, or when facing
downhill in R (Reverse). The vehicle must
come to a complete stop on a grade for HSA
to activate.
Ride Control Systems
Traction Control/Electronic
Stability Control
System Operation
The vehicle has a Traction Control System
(TCS) and StabiliTrak/Electronic Stability
Control (ESC), an electronic stability control system. These systems help limit wheel slip
and assist the driver in maintaining control,
especially on slippery road conditions.
TCS activates if it senses that any of the
drive wheels are spinning or beginning to
lose traction. When this happens, TCS
applies the brakes to the spinning wheels
and reduces engine power to limit
wheel spin.
StabiliTrak/ESC activates when the vehicle
senses a difference between the intended
path and the direction the vehicle is actually
traveling. StabiliTrak/ESC selectively applies
braking pressure to any one of the vehicle
wheel brakes to assist the driver in keeping
the vehicle on the intended path.
If cruise control is being used and TCS or
StabiliTrak/ESC begins to limit wheel spin,
cruise control will disengage. Cruise control
may be turned back on when road
conditions allow.
Both systems come on automatically when
the vehicle is started and begins to move.
The systems may be heard or felt while
they are operating or while performing
diagnostic checks. This is normal and does
not mean there is a problem with the
vehicle.

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
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218 Driving and Operating
The HDC light displays on the instrument
cluster when enabled.
HDC can maintain vehicle speeds between
3 and 22 km/h (2 and 14 mph) on an incline
greater than or equal to a 10% grade.
A blinking HDC light indicates the system is
actively applying the brakes to maintain
vehicle speed.
When HDC is activated, the initial HDC
speed is set to the current driving speed.
It can be increased or decreased by pressing
+RES or–SET on the steering wheel or by
applying the accelerator or brake pedal. This
adjusted speed becomes the new set speed.
HDC will remain enabled between 22 and
60 km/h (14 and 37 mph); however vehicle
speed cannot be set or maintained in this
range. It will automatically disable if the
vehicle speed is above 80 km/h (50 mph) or
above 60 km/h (37 mph) for at least
30 seconds. Press
5again to re-enable HDC.
Driver Mode Control
Depending on the option package and
available features, the Driver Mode Control
can have the following modes: Tour
(Front-Wheel Drive (FWD)), All-Wheel Drive
(AWD), Snow/Ice, Off-Road, and Tow/Haul.
Rotate the Driver Mode Control knob on the
center console to make a mode selection.
Continue turning the knob through the
available modes. Upon selection of a mode,
the selected mode’s icon will light up on the
knob and a message will be displayed in the
Driver Information Center (DIC).
Driver Mode Control Knob for Front-Wheel
Drive (FWD)
Driver Mode Control Knob for All-Wheel
Drive (AWD)
q(Vehicles without AWD) or5(AWD
equipped vehicles) Tour Mode : Use Tour
Mode during normal driving conditions. Tour
Mode either puts the vehicle in Front-Wheel
Drive (FWD) for AWD vehicles, or is the
normal drive mode for FWD vehicles. Tour
Mode is the most fuel efficient drive mode.
See Driving for Better Fuel Economy 0187.
When selecting Tour Mode, if equipped, the
AWD light will flash briefly while the
system disables, and then stays off.

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
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Driving and Operating 221
automatically disengage. SeeTraction
Control/Electronic Stability Control 0214. If a
collision alert occurs when cruise control is
activated, cruise control is disengaged. See
Forward Collision Alert (FCA) System 0237.
When road conditions allow you to safely
use it again, cruise control can be turned
back on.
Cruise control will disengage if either TCS or
StabiliTrak/ESC is turned off.
If Hill Descent Control (HDC) is engaged,
cruise control disengages. See Hill Descent
Control (HDC) 0217.
If the brakes are applied, cruise control
disengages.5: Press to turn the cruise control system
on and off. A white indicator comes on in
the instrument cluster when cruise control is
turned on.
*: Press to disengage cruise control
without erasing the set speed from memory.
+RES : If there is a set speed in memory,
press briefly to resume that speed or press
and hold to accelerate. If cruise control is
already active, use to increase vehicle speed.
–SET : Press briefly to set the speed and
activate cruise control. If cruise control is
already active, use to decrease vehicle
speed.
Setting Cruise Control
If
5is on when not in use, –SET or +RES
could get bumped and go into cruise when
not desired. Keep
5off when cruise is not
being used.
To set a speed:
1. Press
5to turn the cruise system on.
2. Get up to the desired speed.
3. Press and release –SET. The desired set
speed briefly appears in the instrument
cluster. 4. Remove your foot from the accelerator
pedal.
The cruise control indicator on the
instrument cluster turns green after cruise
control has been set to the desired speed.
See Instrument Cluster (Base and Midlevel)
0 85 or
Instrument Cluster (Uplevel) 088.
Resuming a Set Speed
If the cruise control is set at a desired speed
and then the brakes are applied or
*is
pressed, the cruise control is disengaged
without erasing the set speed from memory.
Once the vehicle speed reaches about
40 km/h (25 mph) or more, briefly press
+RES. The vehicle returns to the previous set
speed.
Increasing Speed While Using Cruise Control
If the cruise control system is already
activated:
.Press and hold +RES on the steering
wheel until the vehicle accelerates to the
desired speed, then release it.
.To increase the speed in small increments,
briefly press +RES. For each press, the
vehicle goes about 1 km/h (1 mph) faster.

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
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Driving and Operating 223
ACC can reduce the need for you to
frequently brake and accelerate, especially
when used on expressways, freeways, and
interstate highways. When used on other
roads, you may need to take over the
control of braking or acceleration more
often.
{Warning
ACC has limited braking ability and may
not have time to slow the vehicle down
enough to avoid a collision with another
vehicle you are following. This can occur
when vehicles suddenly slow or stop
ahead, or enter your lane. Also see
“Alerting the Driver”later in this section.
Complete attention is always required
while driving and you should be ready to
take action and apply the brakes. See
Defensive Driving 0187.
{Warning
ACC will not detect or brake for children,
pedestrians, animals, or other objects.
Do not use ACC when:
.On winding and hilly roads or when
the camera sensor is blocked by snow,
ice, or dirt. The system may not
detect a vehicle ahead. Keep the
windshield and headlamps clean.
.When visibility is poor due to rain,
snow, fog, dirt, insect residue, or dust;
when other foreign objects obscure
the camera’s view; or when the
vehicle in front or oncoming traffic
causes additional environmental
obstructions, such as road spray. ACC
performance is limited under these
conditions.
.On slippery roads where fast changes
in tire traction can cause excessive
wheel slip
.With extremely heavy cargo loaded in
the cargo area or rear seat
.When towing a trailer
J:Press to turn the system on or off. The
indicator turns white on the instrument
cluster when ACC is turned on.
RES+ : Press briefly to resume the previous
set speed or to increase vehicle speed if ACC
is already activated. To increase speed by
about 1 km/h (1 mph), press RES+ briefly. To
increase speed to the next 5 km/h (5 mph)
mark on the speedometer, hold RES+.
SET– :Press briefly to set the speed and
activate ACC or to decrease vehicle speed if
ACC is already activated. To decrease speed
by about 1 km/h (1 mph), press SET– briefly.
To decrease speed to the next 5 km/h
(5 mph) mark on the speedometer,
hold SET–.

GMC Terrain/Terrain Denali Owner Manual(GMNA-Localizing-U.S./Canada/
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224 Driving and Operating
*:Press to disengage ACC without erasing
the selected set speed.
[: Press to select a following gap setting
for ACC of Far, Medium, or Near.
The speedometer reading can be displayed
in either English or metric units.
See Instrument Cluster (Base and Midlevel)
0 85 or
Instrument Cluster (Uplevel) 088. The
increment value used depends on the units
displayed.
Switching Between ACC and Regular Cruise
Control
To switch between ACC and regular cruise
control, press and hold
*. A Driver
Information Display (DIC) message displays.
See Vehicle Messages 0108.
ACC IndicatorRegular Cruise Control
Indicator When ACC is engaged, a green
oindicator
will be lit on the instrument cluster and the
following gap will be displayed. When the
regular cruise control is engaged, a green
Jindicator will be lit on the instrument
cluster; the following gap will not display.
When the vehicle is turned on, the cruise
control mode will be set to the last mode
used before the vehicle was turned off.
{Warning
Always check the cruise control indicator
on the instrument cluster to determine
which mode cruise control is in before
using the feature. If ACC is not active, the
vehicle will not automatically brake for
other vehicles, which could cause a crash
if the brakes are not applied manually.
You and others could be seriously injured
or killed.
Setting Adaptive Cruise Control
If
Jis on when not in use, SET–/RES+
could be pressed by mistake and engage
ACC when not desired. Keep
Joff when
cruise is not being used. Select the set speed desired for ACC. This is
the vehicle speed when no vehicle is
detected in your path.
While the vehicle is moving, ACC will not set
at a speed less than 5 km/h (3 mph),
although the minimum allowable set speed
is 25 km/h (15 mph).
To set ACC while moving:
1. Press
J.
2. Get up to the desired speed.
3. Press and release SET–.
4. Remove foot from the accelerator pedal.
After ACC is set, it may immediately apply
the brakes if a vehicle ahead is detected
closer than the selected following gap.
ACC can also be set while the vehicle is
stopped if ACC is on and the brake pedal is
applied.