2015 BUICK LACROSSE engine

Black plate (44,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
5-44 Instruments and Controls
The low tire pressure warning light
will also come on. SeeTire
Pressure Light on page 5-23.
If a tire pressure message displays,
inflate the tires until the tire pressure
is equal to the values shown on the
Tire and Loading Information label.
See Tires on page 10-42, Vehicle
Load Limits on page 9-10, and Tire
Pressure on page 10-50.
More than one tire pressure
message can be received at a time.
The DIC also shows the tire
pressure values. See Driver
Information Center (DIC) on
page 5-28.
Transmission Messages
SERVICE TRANSMISSION
This message displays if there is a
problem with the transmission. See
your dealer.
SHIFT TO PARK
This message displays when the
transmission needs to be shifted to
P (Park). This may appear when
attempting to remove the key from
the ignition or from the vehicle if the
vehicle is not in P (Park).
TRANSMISSION HOT —IDLE
ENGINE
This message displays and a chime
sounds if the transmission fluid in
the vehicle gets hot. Driving with the
transmission fluid temperature high
can cause damage to the vehicle.
Stop the vehicle and let it idle to
allow the transmission to cool. This
message clears when the fluid
temperature reaches a safe level.
Vehicle Speed Messages
SPEED LIMIT EXCEEDED
This message is displayed when the
vehicle speed is greater than the
speed warning speed. See "Speed
Warning" under Instrument Cluster
on page 5-8.
SPEED LIMIT SET TO XXX
This message is displayed when the
speed warning is set. See "Speed
Warning" under Instrument Cluster
on page 5-8.
Window Messages
OPEN, THEN CLOSE DRIVER/
PASSENGER WINDOW
This message is displayed when the
window needs to be reprogrammed.
If the vehicle's battery has been
recharged or disconnected, you will
need to program each front window
for the express-up feature to work.
See Power Windows on page 2-20.

Black plate (3,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Lighting 6-3
Automatic Headlamp
System
When the exterior lamp control is
set to AUTO and it is dark enough
outside, the headlamps come on
automatically.
There is a light sensor on top of the
instrument panel. Do not cover the
sensor; otherwise the headlamps
will come on when they are not
needed.
The system may also turn on the
headlamps when driving through a
parking garage or tunnel.If the vehicle is started in a dark
garage, the automatic headlamp
system comes on immediately. If it
is light outside when the vehicle
leaves the garage, there is a slight
delay before the automatic
headlamp system changes to the
DRL. During that delay, the
instrument cluster may not be as
bright as usual. Make sure the
instrument panel brightness control
is in the full bright position. See
Instrument Panel Illumination
Control on page 6-5.
When it is bright enough outside,
the headlamps will turn off or may
change to Daytime Running
Lamps (DRL).
The automatic headlamp system
turns off when the exterior lamp
control is turned to
Oor the ignition
is off.
Lights On with Wipers
If the windshield wipers are
activated in daylight with the engine
on, and the exterior lamp control is in AUTO, the headlamps, parking
lamps, and other exterior lamps
come on. The transition time for the
lamps coming on varies based on
wiper speed. When the wipers are
not operating, these lamps turn off.
Move the exterior lamp control to
P
or;to disable this feature.
Adaptive Forward
Lighting (AFL)
The AFL pivots the headlamps
horizontally to provide greater road
illumination while turning. To enable
AFL, set the exterior lamp control to
the AUTO position. Moving the
switch out of the AUTO position
deactivates the system. AFL
operates when the vehicle speed is
greater than 3 km/h (2 mph). AFL
does not operate when the
transmission is in R (Reverse). AFL
is not immediately operable after
starting the vehicle; driving a short
distance is required to calibrate the
AFL. See
Exterior Lamp Controls on
page 6-1.

Black plate (7,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Lighting 6-7
Exit Lighting
The headlamps, taillamps, back-up
lamps, parking lamps, and license
plate lamps come on at night, or in
areas with limited lighting, when the
key is removed from the ignition.
The dome lamps also come on
when the key is removed from the
ignition. The exterior lamps and
dome lamps remain on after the
door is closed for a set amount of
time, then automatically turn off.
If equipped with Keyless Access,
the exterior lamps and dome lamps
automatically turn on when the
driver door is opened after the
ignition is turned off. SeeIgnition
Positions (Key Access) on
page 9-15 orIgnition Positions
(Keyless Access) on page 9-16.
The exterior lamps turn off
immediately by turning the exterior
lamp control off.
This feature can be changed. See
Vehicle Personalization on
page 5-45.
Battery Load
Management
The vehicle has Electric Power
Management (EPM) that estimates
the battery's temperature and state
of charge. It then adjusts the voltage
for best performance and extended
life of the battery.
When the battery's state of charge
is low, the voltage is raised slightly
to quickly bring the charge back up.
When the state of charge is high,
the voltage is lowered slightly to
prevent overcharging. If the vehicle
has a voltmeter gauge or a voltage
display on the Driver Information
Center (DIC), you may see the
voltage move up or down. This is
normal. If there is a problem, an
alert will be displayed.
The battery can be discharged at
idle if the electrical loads are very
high. This is true for all vehicles.
This is because the generator
(alternator) may not be spinning fast enough at idle to produce all of the
power needed for very high
electrical loads.
A high electrical load occurs when
several of the following are on, such
as: headlamps, high beams, fog
lamps, rear window defogger,
climate control fan at high speed,
heated seats, engine cooling fans,
trailer loads, and loads plugged into
accessory power outlets.
EPM works to prevent excessive
discharge of the battery. It does this
by balancing the generator's output
and the vehicle's electrical needs.
It can increase engine idle speed to
generate more power whenever
needed. It can temporarily reduce
the power demands of some
accessories.
Normally, these actions occur in
steps or levels, without being
noticeable. In rare cases at the
highest levels of corrective action,
this action may be noticeable to the
driver. If so, a DIC message might
be displayed and it is recommended

Black plate (4,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
8-4 Climate Controls
The indicator will be lit green in eco,
amber in comfort, and turns off
when there is no A/C function. If the
fan is turned off the A/C will not run.
The eco A/C setting balances fuel
economy and air conditioning
comfort. In warm weather
conditions, auto stops may occur
more frequently and the vehicle
interior may be warmer as
compared to the comfort air
conditioning. This setting allows
higher humidity inside the vehicle
and window fogging before the
engine restarts.
Pressing the
0button during an
auto stop may restart the engine to
prevent window fogging. To reach
comfort levels quickly during an
auto stop, the engine will restart if
the air conditioner is off and AUTO
or A/C is selected.
If temperature controls are adjusted
cooler by more than 1°C (1°F)
during an auto stop, the engine will
restart to ensure that comfort is
reached.
@(Recirculation): Press to turn
on recirculation. An indicator light
comes on. Air is recirculated to
quickly cool the air inside the
vehicle or prevent odors from
entering. Press again to change to
outside air and the indicator light
turns off.
Press AUTO to return to automatic
operation and recirculation runs
automatically as needed. The
indicator light is off.
The Air Quality Sensor may operate
the recirculation mode automatically.
See “Climate and Air Quality” under
Vehicle Personalization on
page 5-45.
Auto Defog: The climate control
system may have a sensor to
automatically detect high humidity
inside the vehicle. When high
humidity is detected, the climate
control system may adjust to
outside air supply and turn on the
air conditioner. The fan speed may
slightly increase to help prevent
fogging. If the climate control system does not detect possible
window fogging, it returns to normal
operation. For eAssist vehicles,
there may be shorter and less
frequent auto stops when auto
defog is in use.
To turn Auto Defog off or on, see
“Climate and Air Quality”
under
Vehicle Personalization on
page 5-45.
Rear Window Defogger
=(Rear Window Defogger):
Press to turn the rear window
defogger on or off. An indicator light
on the button comes on to show that
the rear window defogger is on.
The defogger can be turned off by
turning the ignition to ACC/
ACCESSORY or LOCK/OFF.
The rear window defogger can be
set to automatic operation. See
“Climate and Air Quality” under
Vehicle Personalization on
page 5-45. When auto rear defog is
selected, the rear window defogger
turns on automatically when the

Black plate (1,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Driving and Operating 9-1
Driving and
Operating
Driving Information
Distracted Driving . . . . . . . . . . . . . 9-2
Defensive Driving . . . . . . . . . . . . . 9-3
Drunk Driving . . . . . . . . . . . . . . . . . 9-3
Control of a Vehicle . . . . . . . . . . . 9-3
Braking . . . . . . . . . . . . . . . . . . . . . . . 9-3
Steering . . . . . . . . . . . . . . . . . . . . . . . 9-4
Off-Road Recovery . . . . . . . . . . . . 9-5
Loss of Control . . . . . . . . . . . . . . . . 9-6
Driving on Wet Roads . . . . . . . . . 9-6
Hill and Mountain Roads . . . . . . 9-7
Winter Driving . . . . . . . . . . . . . . . . . 9-8
If the Vehicle Is Stuck . . . . . . . . . 9-9
Vehicle Load Limits . . . . . . . . . . 9-10
Starting and Operating
New Vehicle Break-In . . . . . . . . 9-14
Ignition Positions (KeyAccess) . . . . . . . . . . . . . . . . . . . . 9-15
Ignition Positions (Keyless Access) . . . . . . . . . . . . . . . . . . . . 9-16
Starting the Engine . . . . . . . . . . 9-18
Engine Heater . . . . . . . . . . . . . . . 9-22 Retained Accessory
Power (RAP) . . . . . . . . . . . . . . . 9-23
Shifting Into Park . . . . . . . . . . . . 9-24
Shifting out of Park . . . . . . . . . . 9-25
Parking over Things That Burn . . . . . . . . . . . . . . . . . . 9-25
Engine Exhaust
Engine Exhaust . . . . . . . . . . . . . . 9-26
Running the Vehicle WhileParked . . . . . . . . . . . . . . . . . . . . . 9-26
Automatic Transmission
Automatic Transmission . . . . . 9-27
Manual Mode . . . . . . . . . . . . . . . . 9-29
Drive Systems
All-Wheel Drive . . . . . . . . . . . . . . 9-30
Brakes
Antilock BrakeSystem (ABS) . . . . . . . . . . . . . . 9-30
Parking Brake . . . . . . . . . . . . . . . 9-31
Brake Assist . . . . . . . . . . . . . . . . . 9-33
Hill Start Assist (HSA) . . . . . . . 9-33
Ride Control Systems
Traction Control/Electronic Stability Control . . . . . . . . . . . . 9-34
Limited-Slip Differential . . . . . . 9-36
Selective Ride Control . . . . . . . 9-36
Cruise Control
Cruise Control . . . . . . . . . . . . . . . 9-37
Adaptive Cruise Control . . . . . 9-39
Driver Assistance Systems
Driver Assistance Systems . . . . . . . . . . . . . . . . . . . . 9-47
Assistance Systems for Parking or Backing . . . . . . . . . 9-48
Assistance Systems for Driving . . . . . . . . . . . . . . . . . . . . . 9-50
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . . . . . . 9-50
Active Emergency Braking System . . . . . . . . . . . . . . . . . . . . . 9-53
Side Blind Zone Alert (SBZA) . . . . . . . . . . . . . . . 9-54
Lane Change Alert . . . . . . . . . . . 9-55
Lane Departure Warning (LDW) . . . . . . . . . . . . . 9-57

Black plate (4,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
9-4 Driving and Operating
If the engine ever stops while the
vehicle is being driven, brake
normally but do not pump the
brakes. Doing so could make the
pedal harder to push down. If the
engine stops, there will be some
power brake assist but it will be
used when the brake is applied.
Once the power assist is used up, it
can take longer to stop and the
brake pedal will be harder to push.
Steering
Electric Power Steering
If the vehicle has electric power
steering it does not have power
steering fluid. Regular maintenance
is not required.
If power steering assist is lost due
to a system malfunction, the vehicle
can be steered, but may require
increased effort.
See your dealer if there is a
problem.If the steering wheel is turned until it
reaches the end of its travel and is
held against that position for an
extended period of time, power
steering assist may be reduced.
If the steering assist is used for an
extended period of time, power
assist may be reduced.
Normal use of the power steering
assist should return when the
system cools down.
See specific vehicle steering
messages under
Vehicle Messages
on page 5-35.Variable Effort Steering
Some vehicles have a steering
system that varies the amount of
effort required to steer the vehicle in
relation to the speed of the vehicle.
The amount of steering effort
required is less at slower speeds to
make the vehicle more
maneuverable and easier to park. At
faster speeds, the steering effort increases to provide a sport-like feel
to the steering. This provides
maximum control and stability.
If the vehicle seems harder to steer
than normal when parking or driving
slowly, there may be a problem with
the system. You will still have power
steering, but steering will be stiffer
than normal at slow speeds. See
your dealer for service.
Hydraulic Power Steering
If the vehicle has hydraulic power
steering, it may require
maintenance. See
Power Steering
Fluid (2.4L L4 Engine and 3.6L
V6 Engine with FWD) on
page 10-23 orPower Steering Fluid
(3.6L V6 Engine with AWD) on
page 10-23.
If power steering assist is lost
because the engine stops or a
system malfunction, the vehicle can
be steered but may require
increased effort. See your dealer if
there is a problem.

Black plate (7,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Driving and Operating 9-7
Warning (Continued)
Flowing or rushing water creates
strong forces. Driving through
flowing water could cause the
vehicle to be carried away. If this
happens, you and other vehicle
occupants could drown. Do not
ignore police warnings and be
very cautious about trying to drive
through flowing water.
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 on
page 10-42.
.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 for
driving in these conditions 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. Always have the
engine running and the vehicle
in gear.

Black plate (8,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
9-8 Driving and Operating
.Stay in your own lane. Do not
swing wide or cut across the
center of the road. Drive at
speeds that let you stay in your
own lane.
.Be alert on top of hills;
something could be in your lane
(stalled car, accident).
.Pay attention to special road
signs (falling rocks area, winding
roads, long grades, passing or
no-passing zones) and take
appropriate action.
Winter Driving
Driving on Snow or Ice
Drive carefully when there is snow
or ice between the tires and the
road, creating less traction or grip.
Wet ice can occur at about 0°C (32°
F) when freezing rain begins to fall,
resulting in even less traction. Avoid
driving on wet ice or in freezing rain
until roads can be treated with salt
or sand.Drive with caution, whatever the
condition. Accelerate gently so
traction is not lost. Accelerating too
quickly causes the wheels to spin
and makes the surface under the
tires slick, so there is even less
traction.
Traction Control should be turned
on. See
Traction Control/Electronic
Stability Control on page 9-34.
The Antilock Brake System (ABS)
improves vehicle stability during
hard stops on slippery roads, but
apply the brakes sooner than when
on dry pavement. See Antilock
Brake System (ABS) on page 9-30.
Allow greater following distance on
any slippery road and watch for
slippery spots. Icy patches can
occur on otherwise clear roads in
shaded areas. The surface of a
curve or an overpass can remain icy
when the surrounding roads are
clear. Avoid sudden steering
maneuvers and braking while
on ice. Turn off cruise control on slippery
surfaces.
Blizzard Conditions
Being stuck in snow can be a
serious situation. Stay with the
vehicle unless there is help nearby.
If possible, use Roadside
Assistance. See
Roadside
Assistance Program on page 13-5.
To get help and keep everyone in
the vehicle safe:
.Turn on the hazard warning
flashers.
.Tie a red cloth to an outside
mirror.
{Warning
Snow can trap engine exhaust
under the vehicle. This may
cause exhaust gases to get
inside. Engine exhaust contains
carbon monoxide (CO) which
(Continued)