brake BUICK LACROSSE 2017 Service Manual

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
Driving and Operating 193
automatically disengage. See
Traction Control/Electronic Stability
Control0190. If a collision alert
occurs when cruise control is
activated, cruise control is
disengaged. See Forward Collision
Alert (FCA) System 0207. 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 is
turned off.
If the brakes are applied, cruise
control disengages.5: Press to turn cruise control on
or off. A white indicator comes on in
the instrument cluster.
RES+ : 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 engaged, use to
increase vehicle speed.
SET− :Press the control down
briefly to set the speed and activate
cruise control. If cruise control is
already engaged, use to decrease
vehicle speed.
*: Press to disengage cruise
control without erasing the set
speed from memory.
The speedometer reading can be
displayed in either English or metric
units. See Instrument Cluster 0108.
The increment value used depends
on the units displayed.
Setting Cruise Control
If
5is on when not in use, SET− or
RES+ could get pressed and go into
cruise when not desired. Keep
5
off when cruise is not being used. 1. Press
5to turn the cruise
system on.
2. Get to the speed desired.
3. Press and release SET− . 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 0108.
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.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
194 Driving and Operating
Increasing Speed While Using
Cruise Control
Do one of the following:
.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.
Reducing Speed While Using
Cruise Control
Do one of the following:
. 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. Passing Another Vehicle While
Using Cruise Control
Use the accelerator pedal to
increase the vehicle speed. When
you take your foot off the pedal, the
vehicle will slow down to the
previously set cruise speed. While
pressing the accelerator pedal or
shortly following the release to
override cruise control, briefly
pressing SET−
will result in cruise
set to the current vehicle speed.
Using Cruise Control on Hills
How well the cruise control will work
on hills depends upon the vehicle
speed, load, and the steepness of
the hills. When going up steep hills,
you might have to step on the
accelerator pedal to maintain your
speed. When going downhill, you
might have to brake or shift to a
lower gear to keep your speed
down. If the brake pedal is applied,
cruise control will disengage.
Ending Cruise Control
There are four ways to end cruise
control:
. Step lightly on the brake pedal. .
Press*.
. Shift the transmission to
N (Neutral).
. To turn off cruise control,
press
5.
Erasing Speed Memory
The cruise control set speed is
erased from memory if
5is pressed
or the ignition is turned off.
Adaptive Cruise Control
If equipped with Adaptive Cruise
Control (ACC), it allows for selecting
the cruise control set speed and
following gap. Read this entire
section before using this system.
ACC uses a radar sensor to detect
other vehicles. See Radio
Frequency Statement 0321. The
following gap is the following time
(or distance) between your vehicle
and a vehicle detected directly
ahead in your path, moving in the
same direction. If no vehicle is
detected in your path, ACC works
like regular cruise control.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
Driving and Operating 195
If a vehicle is detected in your path,
ACC can speed up the vehicle or
apply limited, moderate braking to
maintain the selected following gap.
To disengage ACC, apply the brake.
If the Traction Control System (TCS)
or StabiliTrak
®electronic stability
control system activates while ACC
is engaged, ACC may automatically
disengage. See Traction Control/
Electronic Stability Control 0190.
When road conditions allow ACC to
be safely used, ACC can be turned
back on. ACC will not engage if the
TCS or StabiliTrak electronic
stability control system is disabled.
{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
(Continued)
Warning (Continued)
always required while driving and
you should be ready to take
action and apply the brakes. See
Defensive Driving0164.
{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 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. ACC
performance is limited under
these conditions.
(Continued)
Warning (Continued)
.On slippery roads where
fast changes in tire traction
can cause excessive
wheel slip.
5:Press to turn the system on or
off. The indicator turns white on the
instrument cluster when ACC is
turned on.
RES+ : Press the control up briefly
to make the vehicle resume to a
previously set speed, or hold

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
196 Driving and Operating
upwards to accelerate. If cruise
control is already engaged, use to
increase vehicle speed.
SET–:Press the control down
briefly to set the speed and activate
cruise control. If cruise control is
already engaged, use to decrease
vehicle speed.
*: Press to disengage ACC
without erasing the selected set
speed.
[: Press to select a following gap
time (or distance) setting for ACC of
Far, Medium, or Near.
The speedometer reading can be
displayed in either English or metric
units. See Instrument Cluster 0108.
The increment value used depends
on the units displayed.
Setting Adaptive Cruise Control
If
5is on when not in use, it could
get pressed and go into ACC when
not desired. Keep
5off when
cruise is not being used. Select the set speed desired for
ACC. 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
5.
2. Get up to the desired speed.
3. Press and release SET–.
4. Remove your 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 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. The vehicle returns
to the previously set speed.
Increasing Speed While ACC is at
a Set Speed
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.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
Driving and Operating 197
When the accelerator pedal is
pressed, ACC will not brake
because it is overridden.
A warning message will appear
on the Driver Information Center
(DIC) and Head-Up Display
(HUD). SeeCruise Control
Messages 0130.
. Press and hold RES+ up until
the desired set speed appears
on the display, then release it.
. To increase vehicle speed in
small increments, briefly press
RES+. For each press, the
vehicle speed increases to the
next 5 km/h (1 mph) mark on the
speedometer.
When it is determined that there is
no vehicle ahead or the vehicle
ahead is beyond the selected
following gap, then the vehicle
speed will increase to the set speed.
Reducing Speed While ACC is at a
Set Speed
Do one of the following:
. Use the brake to get to the
desired lower speed. Press
SET– down and release the accelerator pedal. The vehicle
will now cruise at the lower
speed.
. Press and hold SET– down until
the desired lower speed is
reached, then release it.
. To decrease the vehicle speed in
smaller increments, press SET−
down briefly. For each press, the
vehicle speed decreases to the
next 5 km/h (1 mph) mark on the
speedometer.
Selecting the Follow Distance Gap
When a slower moving vehicle is
detected ahead within the selected
following gap, ACC will adjust the
vehicle's speed and attempt to
maintain the follow distance gap
selected.
Press
[on the steering wheel to
adjust the following gap. Each press
cycles the gap button through three
settings: Far, Medium, or Near.
When pressed, the current gap
setting displays briefly on the
instrument cluster and HUD. The
gap setting will be maintained until it
is changed. Since each gap setting corresponds
to a following time (Far, Medium,
or Near), the following distance will
vary based on vehicle speed. The
faster the vehicle speed, the further
back your vehicle will follow a
vehicle detected ahead. Consider
traffic and weather conditions when
selecting the following gap. The
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. See
Forward
Collision Alert (FCA) System 0207.
Alerting the Driver

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
198 Driving and Operating
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 0138.
See Defensive Driving 0164.
Approaching and Following a
Vehicle
The vehicle ahead indicator is in the
instrument cluster and HUD display.
The vehicle ahead indicator only
displays when a vehicle is detected
in your vehicle’s path moving in the
same direction. If this indicator 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 following 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
lamps 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
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
(Continued)
Warning (Continued)
stop-and-go traffic or when a
vehicle suddenly appears due to
a vehicle ahead changing lanes.
Your vehicle may not stop and
could cause a crash. Use caution
when using ACC. Your complete
attention is always required while
driving and you should be ready
to take action and apply the
brakes.
ACC Automatically Disengages
ACC may automatically disengage
and the driver will need to manually
apply the brakes to slow the
vehicle when:
. The sensors are blocked.
. The Traction Control System
(TCS) or electronic stability
control system has activated or
been disabled.
. No traffic or other objects are
being detected.
. There is a fault in the system.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
Driving and Operating 199
A message will appear on the DIC
indicating that cruise is disengaging.
The ACC active symbol will not be
displayed when ACC is no longer
active.
Notification to Resume ACC
ACC will maintain a following 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 “Go Notifier” in“Collision/
Detection Systems” underVehicle
Personalization 0138.
When the vehicle ahead drives
away, press RES+ or the
accelerator pedal to resume cruise
control. If stopped for more than
two minutes or if the driver door is
opened and the driver safety belt is unbuckled, ACC automatically
applies the Electric Parking Brake
(EPB) to hold the vehicle. The
Electric Parking Brake status light
will turn on. See
Electric Parking
Brake 0187. To resume ACC and
release the EPB, press the
accelerator pedal.
A DIC warning message may
display indicating to shift to P (Park)
before exiting the vehicle. See
Vehicle Messages 0128.
{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.
{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, a DIC warning
message will indicate that automatic
braking will not occur. See Vehicle
Messages 0128. 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.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
200 Driving and Operating
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.
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, signs, guardrails, and other
stationary objects when entering or
exiting a curve. This is normal
operation. The vehicle does not
need service.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
Driving and Operating 201
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.Do Not Use ACC on Hills and
When Towing a TrailerDo 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 0286.
System operation may also be
limited under snow, heavy rain,
or road spray conditions.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
202 Driving and Operating
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. SeeDefensive Driving
0 164.
(Continued)
Warning (Continued)
Under many conditions, these
systems will not:
. 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.
(Continued)
Warning (Continued)
.Work if the area surrounding
the detection sensor is
damaged or not properly
repaired.
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.