2019 BUICK LACROSSE Driver assist

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
Driving and Operating 195
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.
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.
Brake Assist
The Brake Assist feature is
designed to assist the driver in
stopping or decreasing vehicle
speed in emergency driving
conditions. This feature uses the
stability system hydraulic brake
control module to supplement the
power brake system underconditions where the driver has
quickly and forcefully applied the
brake pedal in an attempt to quickly
stop or slow down the vehicle. The
stability system hydraulic brake
control module increases brake
pressure at each corner of the
vehicle until the ABS activates.
Minor brake pedal pulsation or
pedal movement during this time is
normal and the driver should
continue to apply the brake pedal as
the driving situation dictates. The
Brake Assist feature will
automatically disengage when the
brake pedal is released or brake
pedal pressure is quickly
decreased.
Hill Start Assist (HSA)
The Hill Start Assist (HSA) feature
will activate when the vehicle is
stopped on a moderate to steep
grade to help prevent it from rolling
in an unintended direction. After the
brake pedal has been released and
before the accelerator pedal has
been pressed, HSA uses braking
pressure to hold the vehiclestationary. If HSA is holding the
vehicle, a Driver Information Center
(DIC) message displays. HSA will
not activate in a forward drive gear
when facing downhill, or in
R (Reverse) when facing uphill.
Select the duration of the HSA
feature through vehicle
personalization. See
”Extended Hill
Start Assist” under“Comfort and
Convenience” inVehicle
Personalization 0138. When
Standard Hold is selected, the
vehicle is held stationary for up to
two seconds after the brake pedal is
released. When Extended Hold is
selected, the vehicle is held
stationary for up to five minutes
after the brake pedal is released. In
either case, override the hold
feature by pressing the accelerator
pedal and attempting to drive away.
If Standard Hold is selected, it will
hold the vehicle for two seconds
unless the driver door is opened or
the driver seat belt is unbuckled
after releasing the brake pedal.
If Extended Hold is selected, it will
hold the vehicle for five minutes

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
196 Driving and Operating
unless the driver door is opened
and the driver seat belt is unbuckled
prior to releasing the brake pedal.
When deactivated after five minutes,
or if it is deactivated when the driver
seat belt is unlatched or the driver
door is opened, the Electric Parking
Brake will engage to prevent vehicle
movement.
Regenerative Braking
(eAssist)
Regenerative braking takes some of
the energy from the moving vehicle
and turns it back into electrical
energy. This energy is then stored
back into the high voltage battery
system, contributing to increased
energy efficiency.
The hydraulic disc brakes work with
the regenerative braking to ensure
effective braking, such as when a
high braking demand is requested.
The braking system is computer
controlled and blends the
regenerative braking with the
conventional hydraulic disc brakes
to meet any requirements fordeceleration. The controller
interprets the braking request and
uses regenerative braking,
conventional hydraulic braking, or a
combination of both as necessary.
Because the hydraulic braking
system uses an electronic booster
for boost assist on demand, under
certain conditions a motor noise
may be heard. This is normal
operation.
See
Warning Lights, Gauges, and
Indicators 0113 and Driver
Information Center (DIC) 0131. In
the event of a controller problem,
the brake pedal may be harder to
push and the stopping distance may
be longer.
Ride Control Systems
Traction Control/
Electronic Stability
Control
System Operation
The vehicle has a Traction Control
System (TCS) and StabiliTrak/
Electronic Stability Control (ESC).
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

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
Driving and Operating 197
vehicle wheel brakes to assist the
driver in keeping the vehicle on the
intended path.
If cruise control is being used and
traction control 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.
It is recommended to leave both
systems on for normal driving
conditions, but it may be necessary
to turn TCS off if the vehicle gets
stuck in sand, mud, ice, or snow.
SeeIf the Vehicle Is Stuck 0171
and “Turning the Systems Off and
On” later in this section.
The indicator light for both systems
is in the instrument cluster. This
light will:
.
Flash when TCS is limiting
wheel spin.
. Flash when StabiliTrak/ESC is
activated.
. Turn on and stay on when either
system is not working.
If either system fails to turn on or to
activate, a message displays in the
Driver Information Center (DIC), and
dcomes on and stays on to
indicate that the system is inactive
and is not assisting the driver in
maintaining control. The vehicle is
safe to drive, but driving should be
adjusted accordingly.
If
dcomes on and stays on:
1. Stop the vehicle. 2. Turn the engine off and wait
15 seconds.
3. Start the engine.
Drive the vehicle. If
dcomes on
and stays on, the vehicle may need
more time to diagnose the problem.
If the condition persists, see your
dealer.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
208 Driving and Operating
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. The
driver will often need to take over
acceleration and braking on steep
hills, especially when towing a
trailer. If the brakes are applied, the
ACC disengages.
Disengaging ACC
There are three ways to
disengage ACC:
.Step lightly on the brake pedal.
. Press
*.
. Press
5.
Erasing Speed Memory
The cruise control set speed is
erased from memory if
5is pressed
or if the ignition is turned off.
Cleaning the Sensing System
The radar sensor on the front of the
vehicle can become blocked by
snow, ice, dirt, or mud. This area
needs to be cleaned for ACC to
operate properly. For cleaning instructions, see
“Washing the Vehicle”
under
Exterior Care 0309.
System operation may also be
limited under snow, heavy rain,
or road spray conditions.
Driver Assistance
Systems
This vehicle may have features that
work together to help avoid crashes
or reduce crash damage while
driving, backing, and parking. Read
this entire section before using
these systems.
{Warning
Do not rely on the Driver
Assistance Systems. These
systems do not replace the need
for paying attention and driving
safely. You may not hear or feel
alerts or warnings provided by
these systems. Failure to use
proper care when driving may
result in injury, death, or vehicle
damage. See Defensive Driving
0 166.
Under many conditions, these
systems will not: (Continued)

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
Driving and Operating 209
Warning (Continued)
.Detect children,
pedestrians, bicyclists,
or animals.
. Detect vehicles or objects
outside the area monitored
by the system.
. Work at all driving speeds.
. Warn you or provide you
with enough time to avoid a
crash.
. Work under poor visibility or
bad weather conditions.
. Work if the detection sensor
is not cleaned or is covered
by ice, snow, mud, or dirt.
. Work if the detection sensor
is covered up, such as with
a sticker, magnet, or metal
plate.
. Work if the area surrounding
the detection sensor is
damaged or not properly
repaired.
(Continued)
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 0138.
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
0 138.
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.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
210 Driving and Operating
.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), 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. Rear Vision Camera (RVC)
When the vehicle is shifted into
R (Reverse), the RVC shows an
image of the area behind the vehicle
in the infotainment display. The
previous screen displays when the
vehicle is shifted out of R (Reverse)
after a short delay. To return to the
previous screen sooner, press any
button on the infotainment system,
shift into P (Park), or reach a vehicle
speed of 8 km/h (5 mph).
Press MENU to adjust the display
brightness while viewing the
infotainment display.
1. View Displayed by the
Camera
1. View Displayed by theCamera
2. Corners of the Rear Bumper
Displayed images may be farther or
closer than they appear. The area
displayed is limited and objects that
are close to either corner of the
bumper or under the bumper do not
display.
A warning triangle may appear on
the infotainment display to show
that RPA has detected an object.
This triangle changes from amber to
red and increases in size the closer
the object.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
212 Driving and Operating
Rear Cross Traffic Alert (RCTA)
If equipped, when the vehicle is
shifted into R (Reverse), RCTA
displays a red warning triangle with
a left or right pointing arrow on the
infotainment display to warn of
traffic coming from the left or right.
This system detects objects coming
from up to 20 m (65 ft) from the left
or right side of the vehicle. When an
object is detected, either three
beeps sound from the left or right,
or three Safety Alert Seat pulses
occur on the left or right side,
depending on the direction of the
detected vehicle.
Turning the Features On or Off
Use theXbutton on the center
stack to turn on or off the Front and
Rear Park Assist and the Rear
Cross Traffic Alert (RCTA). The
indicator light in the button comes
on when the features are on and
turns off when the features have
been disabled. RCTA can also be turned off
through vehicle personalization. See
“Collision/Detection Systems”
under
Vehicle Personalization 0138.
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. The Driver Information
Center (DIC) 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
(Continued)
Warning (Continued)
in the parking space, such as
movement of an adjacent vehicle,
or a person or object entering the
parking space. APA does not
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 stack 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.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
216 Driving and Operating
timing. The range of selectable alert
timing may not be appropriate for all
drivers and driving conditions.
Changing the FCA timing setting
automatically changes the following
gap setting (Far, Medium, or Near)
for the Adaptive Cruise Control
(ACC) feature.
Following Distance Indicator
The following distance to a moving
vehicle you are following is
indicated in following time in
seconds on the DIC. SeeDriver
Information Center (DIC) 0131. 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, cleaning the
outside of the windshield in front of
the camera sensor and the front of
the vehicle may correct the issue.
Forward Automatic
Braking (FAB)
If the vehicle has Adaptive Cruise
Control (ACC), 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 0214.
The system works when driving in a
forward gear between 10 km/h
(6 mph) and 180 km/h (112 mph) for
moving vehicles, or between
10 km/h (6 mph) and 55 km/h
(34 mph) for stationary vehicles.
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: . Detect a vehicle ahead on
winding or hilly roads.
(Continued)