brakes BUICK LACROSSE 2015 User Guide

Black plate (25,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Driving and Operating 9-25
If you are towing a trailer and
parking on a hill, seeDriving
Characteristics and Towing Tips on
page 9-63.
Shifting out of Park
Automatic Transmission
Shift Lock
The vehicle has an automatic
transmission shift lock control
system. The shift lock control
system is designed to:
.Prevent ignition key removal
unless the shift lever is in
P (Park).
.Prevent movement of the shift
lever out of P (Park), unless the
ignition is in ON/RUN and the
brake pedal is applied.
The shift lock is always functional
except in the case of an uncharged
or low voltage (less than 9‐volt)
battery. If the vehicle has an uncharged
battery or a battery with low voltage,
try charging or jump starting the
battery. See
Jump Starting
(On-board with eAssist Only) on
page 10-78 orJump Starting (with
or without eAssist) on page 10-79.
If the shift lever cannot be moved
out of P (Park):
1. Apply and maintain the regular brakes.
2. Turn the ignition to the ON/RUN position. See Ignition Positions
(Key Access) on page 9-15 or
Ignition Positions (Keyless
Access) on page 9-16 for more
information.
3. Let up on the shift lever and make sure the shift lever is
pushed all the way into P (Park).
4. Press the shift lever button.
5. Move the shift lever into the desired gear. If you still cannot move the shift
lever from P (Park), consult your
dealer or a professional towing
service.
Parking over Things
That Burn
{Warning
Things that can burn could touch
hot exhaust parts under the
vehicle and ignite. Do not park
over papers, leaves, dry grass,
or other things that can burn.

Black plate (30,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
9-30 Driving and Operating
engine rpm is too high, nor to the
next higher gear when the maximum
engine rpm is reached.
While in Manual Mode, the
transmission will automatically
downshift when the vehicle comes
to a stop. This will allow for more
power during take-off.
When accelerating the vehicle from
a stop in snowy and icy conditions,
you may want to shift into
2 (Second) gear. A higher gear
allows the vehicle to gain more
traction on slippery surfaces.Drive Systems
All-Wheel Drive
Vehicles with this feature always
send engine power to all four
wheels. It is fully automatic, and
adjusts itself as needed for road
conditions.
All-Wheel Drive (AWD) system
performance will be automatically
reduced when the compact spare
tire is in use. To restore full AWD
performance, and prevent excessive
wear to the AWD system, replace
the compact spare tire with a
full-size tire as soon as possible.
SeeCompact Spare Tire on
page 10-77.
Brakes
Antilock Brake
System (ABS)
This vehicle has ABS, an advanced
electronic braking system that helps
prevent a braking skid.
When the vehicle begins to drive
away, ABS checks itself.
A momentary motor or clicking noise
might be heard while this test is
going on, and it might even be
noticed that the brake pedal moves
a little. This is normal.
If there is a problem with ABS, this
warning light stays on. See Antilock
Brake System (ABS) Warning Light
on page 5-20.

Black plate (31,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Driving and Operating 9-31
If driving safely on a wet road and it
becomes necessary to slam on the
brakes and continue braking to
avoid a sudden obstacle, a
computer senses the wheels are
slowing down. If one of the wheels
is about to stop rolling, the computer
will separately work the brakes at
each wheel.
ABS can change the brake pressure
to each wheel, as required, faster
than any driver could. This can help
you steer around the obstacle while
braking hard.
As the brakes are applied, the
computer keeps receiving updates
on wheel speed and controls
braking pressure accordingly.
Remember: ABS does not change
the time needed to get a foot up to
the brake pedal or always decrease
stopping distance. If you get too
close to the vehicle in front of you,
there will not be enough time to
apply the brakes if that vehiclesuddenly slows or stops. Always
leave enough room up ahead to
stop, even with ABS.
Using ABS
Do not pump the brakes. Just hold
the brake pedal down firmly and let
ABS work. You may hear the ABS
pump or motor operating and feel
the brake pedal pulsate. This is
normal.
Braking in Emergencies
ABS allows you to steer and brake
at the same time. In many
emergencies, steering can help
more than even the very best
braking.
Parking Brake
The Electric Parking Brake (EPB)
switch is on the center console. The
EPB can always be activated, even
if the ignition is off. To prevent
draining the battery, avoid repeated
cycles of the EPB when the engine
is not running.
The system has a red parking brake
status light and an amber parking
brake warning light. See
Electric
Parking Brake Light on page 5-20
and Service Electric Parking Brake
Light on page 5-20. There are also

Black plate (33,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Driving and Operating 9-33
Caution (Continued)
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.
If parking on a hill, or if the vehicle
is pulling a trailer, seeDriving
Characteristics and Towing Tips on
page 9-63.
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 under
conditions 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)
This vehicle has an HSA feature,
which may be useful when the
vehicle is stopped on a grade
sufficient enough to activate HSA.
This feature is designed to prevent
the vehicle from rolling, either
forward or rearward, during vehicle
drive off. After the driver completely
stops and holds the vehicle in a
complete standstill on a grade, HSA
will be automatically activated.
During the transition period between
when the driver releases the brake
pedal and starts to accelerate to
drive off on a grade, HSA holds the
braking pressure for a maximum of
two seconds to ensure that there is
no rolling. The brakes will
automatically release when the
accelerator pedal is applied within
the two-second window. It will not
activate if the vehicle is in a drive
gear and facing downhill, or if the
vehicle is facing uphill and in
R (Reverse).

Black plate (34,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
9-34 Driving and Operating
Ride Control Systems
Traction Control/
Electronic Stability
Control
System Operation
The vehicle has a Traction Control
System (TCS) and StabiliTrak®, 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 activates when the
vehicle senses a difference between
the intended path and the direction
the vehicle is actually traveling.
StabiliTrak 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
traction control or StabiliTrak 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.
See
If the Vehicle Is Stuck on
page 9-9 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 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.

Black plate (37,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Driving and Operating 9-37
Cruise Control
With cruise control the vehicle can
maintain a speed of about 40 km/h
(25 mph) or more without keeping
your foot on the accelerator. Cruise
control does not work at speeds
below 40 km/h (25 mph).
{Warning
Cruise control can be dangerous
where you cannot drive safely at
a steady speed. Do not use
cruise control on winding roads or
in heavy traffic.
Cruise control can be dangerous
on slippery roads. On such roads,
fast changes in tire traction can
cause excessive wheel slip, and
you could lose control. Do not use
cruise control on slippery roads.If equipped with the Traction Control
System (TCS), the system may
begin to limit wheel spin while you
are using cruise control. If this
happens, the cruise control will
automatically disengage. See
Traction Control/Electronic Stability
Control on page 9-34. If a collision
alert occurs when cruise control is
activated, cruise control is
disengaged. See
Forward Collision
Alert (FCA) System on page 9-50.
When road conditions allow you to
safely use it again, cruise control
can be turned back on.
If the brakes are applied, cruise
control disengages.
5(On/Off): Press to turn cruise
control on or off. A white indicator
comes on in the instrument cluster.
RES+ (Resume/Accelerate): If
there is a set speed in memory,
press the control up briefly to
resume to that speed or press and
hold to accelerate. If cruise control
is already active, use to increase
vehicle speed.

Black plate (38,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
9-38 Driving and Operating
SET−(Set/Coast): Press the
control down briefly to set the speed
and activate cruise control. If cruise
control is already active, use to
decrease vehicle speed.
*(Cancel): Press to disengage
cruise control without erasing the
set speed from memory.
Setting Cruise Control
If the
5button is on when not in
use, SET− or RES+ could get
pressed and go into cruise when not
desired. Keep the
5button off
when cruise is not being used.
1. Press the
5button to turn the
cruise system on.
2. Get to the speed desired.
3. Press and release the SET− control on the steering wheel.
The desired set speed briefly
appears in the instrument
cluster.
4. Take your foot off the accelerator pedal. The cruise control indicator on the
instrument cluster turns green after
the cruise control has been set to
the desired speed. See
Instrument
Cluster on page 5-8.
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 reaches about
40 km/h (25 mph) or more, press
RES+ up briefly. The vehicle returns
to the previously set speed.
Increasing Speed While Using
Cruise Control
If the cruise control system is
already activated:
.Press and hold RES+ up until
the vehicle accelerates to the
desired speed, then release it.
.To increase vehicle speed in
small increments, press RES+
up briefly. For each press, the
vehicle goes about 1.6 km/h
(1 mph) faster.
The speedometer reading can be
displayed in either English or metric
units. See Instrument Cluster on
page 5-8. The increment value used
depends on the units displayed.
Reducing Speed While Using
Cruise Control
If the cruise control system is
already activated:
.Press and hold SET− down until
the desired lower speed is
reached, then release it.
.To slow down in small
increments, press SET−down
briefly. For each press, the
vehicle goes about 1.6 km/h
(1 mph) slower.

Black plate (40,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
9-40 Driving and Operating
{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” 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 on page 9-3.
{Warning
Adaptive Cruise Control will not
detect or brake for children,
pedestrians, animals, or other
objects.
(Continued)
Warning (Continued)
Do not use Adaptive Cruise
Control when:
.On winding and hilly roads or
when the sensors are
blocked by snow, ice, or dirt.
The system may not detect a
vehicle ahead. Keep the
entire front of the vehicle
clean.
.Visibility is low, such as in
fog, rain, or snow conditions.
Adaptive Cruise Control
performance is limited under
these conditions.
.On slippery roads where fast
changes in tire traction can
cause excessive wheel slip.
](On/Off):Press to turn the
system on or off. The indicator turns
white on the instrument cluster
when ACC is turned on.
RES+ (Resume/Accelerate):
Press the control up briefly to make
the vehicle resume to a previously
set speed, or hold upwards to
accelerate. If cruise control is
already active, use to increase
vehicle speed.

Black plate (41,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Driving and Operating 9-41
SET–(Set/Coast): Press the
control down briefly to set the speed
and activate cruise control. If cruise
control is already active, use to
decrease vehicle speed.
*(Cancel): Press to disengage
ACC without erasing the selected
set speed.
3(Follow Distance Gap): Press
to select a following gap time (or
distance) setting for ACC of Far,
Medium, or Near.
Setting Adaptive Cruise Control
If the cruise button is on when not in
use, it could get pressed and go into
cruise when not desired. Keep the
cruise control button off when cruise
is not being used.
Select the set speed desired for
cruise. This is the vehicle speed
when no vehicle is detected in
its path.
ACC will not set at a speed less
than 25 km/h (16 mph), although it
can be resumed when driving at
lower speeds. To set ACC:
1. Press
].
2. Get up to the desired speed.
3. Press and release the SET– control on the steering wheel.
4. Remove foot from the accelerator.
After ACC is set, it may immediately
apply the brakes if a vehicle ahead
is detected closer than the selected
following gap.
The ACC indicator displays on the
instrument cluster and Head-Up
Display (HUD). When ACC is active,
the indicator will be lit green. Be mindful of speed limits,
surrounding traffic speeds, and
weather conditions when selecting
the set speed.
Resuming a Set Speed
If the ACC is set at a desired speed
and then the brakes are applied,
ACC is disengaged without erasing
the set speed from memory.
To begin using ACC again, press
RES+ up briefly on the steering
wheel. The vehicle returns to the
previously set speed.
Increasing Speed While ACC is at
a Set Speed
If ACC is already activated, do one
of the following:
.Use the accelerator to get to the
higher speed. Press SET–
down.
Release the control and the
accelerator pedal. The vehicle
will now cruise at the higher
speed.

Black plate (43,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Driving and Operating 9-43
range of selectable gaps may not be
appropriate for all drivers and
driving conditions.
Changing the gap setting
automatically changes the alert
timing sensitivity (Far, Medium,
or Near) for the Forward Collision
Alert (FCA) feature. SeeForward
Collision Alert (FCA) System on
page 9-50.
Alerting the Driver
If ACC is engaged, driver action
may be required when ACC cannot
apply sufficient braking because of
approaching a vehicle too rapidly.
When this condition occurs, the
collision alert symbol on the HUD
will flash on the windshield. Either
eight beeps will sound from the
front, or both sides of the Safety Alert Seat will pulse five times. See
“Collision/Detection Systems”
under
Vehicle Personalization on
page 5-45.
See Defensive Driving on page 9-3.
Approaching and Following a
Vehicle
The vehicle ahead symbol is in the
instrument cluster and HUD display.
The vehicle ahead symbol only
displays when a vehicle is detected
in your vehicle’s path moving in the
same direction.
If this symbol is not displaying, ACC
will not respond to or brake to
vehicles ahead.
ACC automatically slows the vehicle
down and adjusts vehicle speed to
follow the vehicle in front at the selected follow gap. The vehicle
speed increases or decreases to
follow the vehicle in front of you, but
will not exceed the set speed. It may
apply limited braking, if necessary.
When braking is active, the brake
lights will come on. The automatic
braking may feel or sound different
than if the brakes were applied
manually. This is normal.
Stationary or Very Slow-Moving
Objects
{Warning
Adaptive Cruise Control (ACC)
may not detect and react to
stopped or slow-moving vehicles
ahead of you. For example, the
system may not brake for a
vehicle it has never detected
moving. This can occur in
stop-and-go traffic or when a
vehicle suddenly appears due to
a vehicle ahead changing lanes.
Your vehicle may not stop and
(Continued)