service BUICK LACROSSE 2019 Service Manual

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
Driving and Operating 207
{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
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. 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 Trailer

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
Driving and Operating 213
.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 bordered by two
vehicles or other objects, an audible
beep occurs and a red symbol
displays in the DIC.
APA will instruct the vehicle to stop
once a large enough space is found.
Follow the instructions in the DIC.
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 is in R (Reverse), but
does not steer into the expected
space, this may be because the
system is maneuvering the vehicle
into a previously detected space.
The APA system does not need
service.
If the vehicle exceeds 10 km/h
(6 mph), APA is automatically
disengaged and automatic steering
will turn off. A DIC 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.

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)

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
218 Driving and Operating
.There is a problem with the
StabiliTrak/Electronic Stability
Control (ESC) system.
The FAB system does not need
service.
Front Pedestrian Braking
(FPB) System
If equipped, the FPB system may
help avoid or reduce the harm
caused by front-end crashes with
nearby pedestrians when driving in
a forward gear. FPB displays an
amber indicator,
~, when a nearby
pedestrian is detected directly
ahead. When approaching a
detected pedestrian too quickly,
FPB provides a red flashing alert on
the windshield and rapidly beeps or
pulses the driver seat. FPB can
provide a boost to braking or
automatically brake the vehicle. This
system includes Intelligent Brake
Assist (IBA), and the Forward
Automatic Braking (FAB) system
may also respond to pedestrians.
See Forward Automatic Braking
(FAB) 0216. The FPB system can detect and
alert to pedestrians in a forward
gear at speeds between 8 km/h
(5 mph) and 80 km/h (50 mph).
During daytime driving, the system
detects pedestrians up to a distance
of approximately 40 m (131 ft).
During nighttime driving, system
performance is very limited.
{Warning
FPB does not provide an alert or
automatically brake the vehicle,
unless it detects a pedestrian.
FPB may not detect pedestrians,
including children:
. When the pedestrian is not
directly ahead, fully visible,
or standing upright, or when
part of a group.
. Due to poor visibility,
including nighttime
conditions, fog, rain,
or snow.
. If the FPB sensor is blocked
by dirt, snow, or ice.
(Continued)
Warning (Continued)
.If the headlamps or
windshield are not cleaned
or in proper condition.
Be ready to take action and apply
the brakes. For more information,
see Defensive Driving 0166.
Keep the windshield, headlamps,
and FPB sensor clean and in
good repair.
FPB can be set to Off, Alert, or Alert
and Brake through vehicle
personalization. See “Collision/
Detection Systems” underVehicle
Personalization 0138.
Detecting the Pedestrian
Ahead

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
Driving and Operating 219
FPB alerts and automatic braking
will not occur unless the FPB
system detects a pedestrian. When
a nearby pedestrian is detected
directly in front of the vehicle, the
pedestrian ahead indicator will
display amber.
Front Pedestrian Alert
When the vehicle approaches a
pedestrian ahead too rapidly, the
red FPB alert display will flash on
the windshield. Eight rapid
high-pitched beeps will sound from
the front, or both sides of the Safety
Alert Seat will pulse five times.
When this Pedestrian Alert occurs,
the brake system may prepare for
driver braking to occur more rapidly
which can cause a brief, mild
deceleration. Continue to apply thebrake pedal as needed. Cruise
control may be disengaged when
the Front Pedestrian Alert occurs.
Automatic Braking
If FPB detects it is about to crash
into a pedestrian directly ahead, and
the brakes have not been applied,
FPB may automatically brake
moderately or brake hard. This can
help to avoid some very low speed
pedestrian crashes or reduce
pedestrian injury. FPB can
automatically brake to detected
pedestrians between 8 km/h (5 mph)
and 80 km/h (50 mph). Automatic
braking levels may be reduced
under certain conditions, such as
higher speeds.
If this happens, Automatic Braking
may engage the Electric Parking
Brake (EPB) to hold the vehicle at a
stop. Release the EPB. A firm press
of the accelerator pedal will also
release Automatic Braking and
the EPB.
{Warning
FPB may alert or automatically
brake the vehicle suddenly in
situations where it is unexpected
and undesired. It could falsely
alert or brake for objects similar in
shape or size to pedestrians,
including shadows. This is normal
operation and the vehicle does
not need service. To override
Automatic Braking, firmly press
the accelerator pedal, if it is safe
to do so.
Automatic Braking can be disabled
through vehicle personalization. See
“Front Pedestrian Detection” in
“Collision/Detection Systems” under
Vehicle Personalization 0138.
{Warning
Using the Front Pedestrian
Braking system while towing a
trailer could cause you to lose
(Continued)

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
Driving and Operating 221
Side Blind Zone Alert (SBZA)
warning area starts at approximately
the middle of the vehicle and goes
back 5 m (16 ft). Drivers are also
warned of vehicles rapidly
approaching from up to 70 m (230 ft)
behind the vehicle.
How the System Works
The LCA symbol lights up in the
side mirrors when the system
detects a moving vehicle in the next
lane over that is in the side blind
zone or rapidly approaching that
zone from behind. A lit LCA symbol
indicates it may be unsafe to
change lanes. Before making a lane
change, check the LCA display,
check mirrors, glance over your
shoulder, and use the turn signals.
Left Side MirrorDisplayRight Side Mirror Display When the vehicle is started, both
outside mirror LCA displays will
briefly come on to indicate the
system is operating. When the
vehicle is in a forward gear, the left
or right side mirror display will light
up if a moving vehicle is detected in
the next lane over in that blind zone
or rapidly approaching that zone.
If the turn signal is activated in the
same direction as a detected
vehicle, this display will flash as an
extra warning not to change lanes.
LCA can be disabled through
vehicle personalization using the
Lane Change Alert option. See
“Collision/Detection Systems”
under
Vehicle Personalization 0138.
If LCA is disabled by the driver, the
LCA mirror displays will not light up.
When the System Does Not
Seem to Work Properly
The LCA system requires some
driving for the system to calibrate to
maximum performance. This
calibration may occur more quickly if
the vehicle is driving on a straight highway road with traffic and
roadside objects (e.g., guardrails,
barriers).
LCA displays may not come on
when passing a vehicle quickly, for
a stopped vehicle, or when towing a
trailer. The LCA detection zones
that extend back from the side of
the vehicle do not move further back
when a trailer is towed. Use caution
while changing lanes when towing a
trailer. LCA may alert to objects
attached to the vehicle, such as a
trailer, bicycle, or object extending
out to either side of the vehicle.
Attached objects may also interfere
with the detection of vehicles. This
is normal system operation; the
vehicle does not need service.
LCA may not always alert the driver
to vehicles in the next lane over,
especially in wet conditions or when
driving on sharp curves. The system
does not need to be serviced. The
system may light up due to
guardrails, signs, trees, shrubs, and
other non-moving objects. This is
normal system operation; the
vehicle does not need service.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
222 Driving and Operating
LCA may not operate when the LCA
sensors in the left or right corners of
the rear bumper are covered with
mud, dirt, snow, ice, or slush, or in
heavy rainstorms. For cleaning
instructions, see "Washing the
Vehicle" underExterior Care0309.
If the DIC still displays the system
unavailable message after cleaning
both sides of the vehicle toward the
rear corners of the vehicle, see your
dealer.
If the LCA displays do not light up
when moving vehicles are in the
side blind zone or are rapidly
approaching this zone and the
system is clean, the system may
need service. Take the vehicle to
your dealer.
Radio Frequency Information
See Radio Frequency Statement
0 345.
Lane Departure
Warning (LDW)
If equipped, LDW may help avoid
crashes due to unintentional lane
departures. It may provide a
warning if the vehicle is crossing a
detected lane marking without using
a turn signal in the lane departure
direction. Since this system is part
of the Lane Keep Assist (LKA)
system, read the entire LKA section
before using this feature.
Lane Keep Assist (LKA)
If equipped, LKA may help avoid
crashes due to unintentional lane
departures. It may assist by gently
turning the steering wheel if the
vehicle approaches a detected lane
marking without using a turn signal
in that direction. It may also provide
a Lane Departure Warning (LDW)
system alert as the lane marking is
crossed. The LKA system will not
assist or provide an LDW alert if it
detects that you are actively
steering. Override LKA by turning
the steering wheel. LKA uses a camera to detect lane markings
between 60 km/h (37 mph) and
180 km/h (112 mph).
{Warning
The LKA system does not
continuously steer the vehicle.
It may not keep the vehicle in the
lane or give a Lane Departure
Warning (LDW) alert, even if a
lane marking is detected.
The LKA and LDW systems
may not:
. Provide an alert or enough
steering assist to avoid a
lane departure or crash.
. Detect lane markings under
poor weather or visibility
conditions. This can occur if
the windshield or
headlamps are blocked by
dirt, snow, or ice, if they are
not in proper condition, or if
the sun shines directly into
the camera.
(Continued)

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
224 Driving and Operating
A camera blocked message may
display if the camera is blocked.
Cleaning the outside of the
windshield behind the rearview
mirror may correct the issue. Some
driver assistance systems may have
reduced performance or not work at
all. An LKA or LDW unavailable
message may display if the systems
are temporarily unavailable. This
message could be due to a blocked
camera. The LKA system does not
need service. Clean the outside of
the windshield behind the rearview
mirror.
LKA assistance and/or LDW alerts
may occur due to tar marks,
shadows, cracks in the road,
temporary or construction lane
markings, or other road
imperfections. This is normal system
operation; the vehicle does not need
service. Turn LKA off if these
conditions continue.Fuel
Top Tier Fuel
GM recommends the use of TOP
TIER Detergent Gasoline to keep
the engine clean, reduce engine
deposits, and maintain optimal
vehicle performance. Look for the
TOP TIER Logo or see
www.toptiergas.com for a list of TOP
TIER Detergent Gasoline marketers
and applicable countries.
Recommended Fuel
Do not use any fuel labeled E85 or
FlexFuel. Do not use gasoline with
ethanol levels greater than 15% by
volume.
Use regular unleaded gasoline
meeting ASTM specification D4814
with a posted octane rating of 87 or
higher. Do not use gasoline with a
posted octane rating of less than 87,
as this may cause engine knock and
will lower fuel economy.
Prohibited Fuels
Caution
Do not use fuels with any of the
following conditions; doing so
may damage the vehicle and void
its warranty:. For vehicles that are not
FlexFuel, fuel labeled
greater than 15% ethanol by
(Continued)

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
230 Driving and Operating
If parking the rig on a hill:1. Press the brake pedal, but do not shift into P (Park) yet. Turn
the wheels into the curb if
facing downhill or into traffic if
facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the regular
brakes until the chocks absorb
the load.
4. Reapply the brake pedal. Then apply the parking brake and
shift into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
2. Start the engine.
3. Shift into a gear.
4. Release the parking brake.
5. Let up on the brake pedal.
6. Drive slowly until the trailer is clear of the chocks. 7. Stop and have someone pick
up and store the chocks.
Maintenance when Trailer
Towing
The vehicle needs service more
often when pulling a trailer. See
Maintenance Schedule 0320.
Things that are especially important
in trailer operation are automatic
transmission fluid, engine oil, axle
lubricant, belts, cooling system, and
brake system. It is a good idea to
inspect these before and during
the trip.
Check periodically to see that all
hitch nuts and bolts are tight.
Trailer Towing
{Warning
The driver can lose control when
pulling a trailer if the correct
equipment is not used or the
vehicle is not driven properly. For
example, if the trailer is too heavy
(Continued)
Warning (Continued)
or the trailer brakes are
inadequate for the load, the
vehicle may not stop as expected.
The driver and passengers could
be seriously injured. The vehicle
may also be damaged; the
resulting repairs would not be
covered by the vehicle warranty.
Pull a trailer only if all the steps in
this section have been followed.
Ask your dealer for advice and
information about towing a trailer
with the vehicle.
Caution
Pulling a trailer improperly can
damage the vehicle and result in
costly repairs not covered by the
vehicle warranty. To pull a trailer
correctly, follow the advice in this
section and see your dealer for
important information about
towing a trailer with the vehicle.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
Driving and Operating 233
Conversions and
Add-Ons
Add-On Electrical
Equipment
{Warning
The Data Link Connector
(DLC) is used for vehicle service
and Emission Inspection/
Maintenance testing. See
Malfunction Indicator Lamp
(Check Engine Light)0122.
A device connected to the DLC —
such as an aftermarket fleet or
driver-behavior tracking device —
may interfere with vehicle
systems. This could affect vehicle
operation and cause a crash.
Such devices may also access
information stored in the vehicle’s
systems.
Caution
Some electrical equipment can
damage the vehicle or cause
components to not work and
would not be covered by the
vehicle warranty. Always check
with your dealer before adding
electrical equipment.
Add-on equipment can drain the
vehicle's 12-volt battery, even if the
vehicle is not operating.
The vehicle has an airbag system.
Before attempting to add anything
electrical to the vehicle, see
Servicing the Airbag-Equipped
Vehicle 081 and Adding Equipment
to the Airbag-Equipped Vehicle
0 81.