key BUICK LACROSSE 2015 Service Manual

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 (15,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Driving and Operating 9-15
Caution (Continued)
breaking-in guideline every
time you get new brake
linings.
Following break-in, engine speed
and load can be gradually
increased.
Ignition Positions (Key
Access)
{Caution
Using a tool to force the key to
turn in the ignition could cause
damage to the switch or break the
key. Use the correct key, make
sure it is all the way in, and turn it
only with your hand. If the key
cannot be turned by hand, see
your dealer.
The key must be fully extended to
start the vehicle.
To shift out of P (Park), turn the
ignition to ON/RUN and apply the
brake pedal.
1 (STOPPING THE ENGINE/LOCK/
OFF): When the vehicle is stopped,
turn the ignition switch to LOCK/
OFF to turn the engine off. Retained
Accessory Power (RAP) will remain
active. See Retained Accessory
Power (RAP) on page 9-23 for more
information. This is the only position from which
the key can be removed. This locks
the ignition and automatic
transmission.
Do not turn the engine off when the
vehicle is moving. This will cause a
loss of power assist in the brake
and steering systems and disable
the airbags.
If the vehicle must be shut off in an
emergency:
1. Brake using a firm and steady
pressure. Do not pump the
brakes repeatedly. This may
deplete power assist, requiring
increased brake pedal force.
2. Shift the vehicle to N (Neutral). This can be done while the
vehicle is moving. After shifting
to N (Neutral), firmly apply the
brakes and steer the vehicle to a
safe location.
3. Come to a complete stop, shift to P (Park), and turn the ignition
to LOCK/OFF. On vehicles with
an automatic transmission, the

Black plate (16,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
9-16 Driving and Operating
shift lever must be in P (Park) to
turn the ignition switch to the
LOCK/OFF position.
4. Set the parking brake. See Parking Brake on page 9-31.
{Warning
Turning off the vehicle while
moving may cause loss of power
assist in the brake and steering
systems and disable the airbags.
While driving, only shut the
vehicle off in an emergency.
If the vehicle cannot be pulled over,
and must be shut off while driving,
turn the ignition to ACC/
ACCESSORY.
2 (ACC/ACCESSORY): This
position provides power to some of
the electrical accessories. It unlocks
the ignition. To move the key from
ACC/ACCESSORY to LOCK/OFF,
the shift lever must be in P (Park). 3 (ON/RUN):
The ignition switch
stays in this position when the
engine is running. This position can
be used to operate the electrical
accessories, including the
ventilation fan and 12-volt power
outlet, as well as to display some
warning and indicator lights. This
position can also be used for
service and diagnostics, and to
verify the proper operation of the
malfunction indicator lamp as may
be required for emission inspection
purposes. The transmission is also
unlocked in this position.
The battery could be drained if the
key is left in the ACC/ACCESSORY
or ON/RUN position with the engine
off. The vehicle might not restart if
the battery is allowed to drain for an
extended period of time.
4 (START): This position starts the
engine. When the engine starts,
release the key. The ignition switch
will return to ON/RUN for normal
driving. A warning tone sounds when the
driver door is opened when the
ignition is still in ACC/ACCESSORY
and the key is in the ignition. If the
ignition becomes difficult to turn,
see
Keys on page 2-1.
Ignition Positions
(Keyless Access)
The vehicle has an electronic
keyless ignition with pushbutton
start.

Black plate (17,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Driving and Operating 9-17
Pressing the button cycles it through
three modes, ACC/ACCESSORY,
ON/RUN/START, and Stopping the
Engine/OFF.
The transmitter must be in the
vehicle for the system to operate.
If the pushbutton start is not
working, the vehicle may be near a
strong radio antenna signal causing
interference to the keyless access
system. SeeRemote Keyless Entry
(RKE) System Operation on
page 2-3.
To shift out of P (Park), the vehicle
must be in ACC/ACCESSORY or
ON/RUN and the brake pedal must
be applied.
Stopping the Engine/OFF (No
Indicator Lights): When the
vehicle is stopped, press the
ENGINE START/STOP button once
to turn the engine off.
If the vehicle is in P (Park), the
ignition will turn off, and Retained
Accessory Power (RAP) will remain
active. See Retained Accessory
Power (RAP) on page 9-23. If the vehicle is not in P (Park), the
ignition will return to ACC/
ACCESSORY and display the
message SHIFT TO PARK in the
Driver Information Center (DIC).
See
Transmission Messages on
page 5-44. When the vehicle is
shifted into P (Park), the ignition
system will switch to OFF.
Do not turn the engine off when the
vehicle is moving. This will cause a
loss of power assist in the brake
and steering systems and disable
the airbags.
If the vehicle must be shut off in an
emergency:
1. Brake using a firm and steady pressure. Do not pump the
brakes repeatedly. This may
deplete power assist, requiring
increased brake pedal force.
2. Shift the vehicle to N (Neutral). This can be done while the
vehicle is moving. After shifting
to N (Neutral), firmly apply the
brakes and steer the vehicle to a
safe location. 3. Come to a complete stop, shift
to P (Park), and turn the ignition
to OFF. On vehicles with an
automatic transmission, the shift
lever must be in P (Park) to turn
the ignition switch to the OFF
position.
4. Set the parking brake. See Parking Brake on page 9-31.
{Warning
Turning off the vehicle while
moving may cause loss of power
assist in the brake and steering
systems and disable the airbags.
While driving, only shut the
vehicle off in an emergency.
If the vehicle cannot be pulled over,
and must be shut off while driving,
press and hold the ENGINE START/
STOP button for longer than
two seconds, or press twice in
five seconds.

Black plate (19,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Driving and Operating 9-19
{Caution
If the steering wheel is turned
until it reaches the end of its
travel, and is held in that position
while starting the vehicle, damage
may occur to the hydraulic power
steering system and there may be
loss of power steering assist.
Starting Procedure (Key Access)
1. With your foot off the accelerator pedal, turn the ignition key to
START. When the engine starts,
let go of the key.
The idle speed will go down as
the engine warms. Do not race
the engine immediately after
starting it. Allow the oil to warm
up and lubricate all moving
parts.
{Caution
Cranking the engine for long
periods of time, by returning the
ignition to the START position
immediately after cranking has
ended, can overheat and damage
the cranking motor, and drain the
battery. Wait at least 15 seconds
between each try, to let the
cranking motor cool down.
2. If the engine does not start after five to 10 seconds, especially in
very cold weather (below −18°C
or 0°F), it could be flooded with
too much gasoline. Try pushing
the accelerator pedal all the way
to the floor and holding it there
as you hold the key in START
for up to a maximum of
15 seconds. Wait at least
15 seconds between each try, to
allow the cranking motor to cool
down. When the engine starts, let go of the key, and the
accelerator. If the vehicle starts
briefly but then stops again, do
the same thing. This clears the
extra gasoline from the engine.
Do not race the engine
immediately after starting it.
Operate the engine and
transmission gently until the oil
warms up and lubricates all
moving parts.
Starting Procedure (Keyless
Access)
1. With the Keyless Access system, the RKE transmitter
must be in the vehicle. Press the
ENGINE START/STOP button
with the brake pedal applied.
When the engine begins
cranking, let go of the button.
The idle speed will go down as
the engine gets warm. Do not
race the engine immediately
after starting it.

Black plate (20,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
9-20 Driving and Operating
If the RKE transmitter is not in
the vehicle, if there is
interference, or the RKE battery
is low, the Driver Information
Center (DIC) will display a
message. SeeKey and Lock
Messages on page 5-39 and
Remote Keyless Entry (RKE)
System Operation on page 2-3.
{Caution
Cranking the engine for long
periods of time, by returning the
ignition to the START position
immediately after cranking has
ended, can overheat and damage
the cranking motor, and drain the
battery. Wait at least 15 seconds
between each try, to let the
cranking motor cool down.
2. If the engine does not start after five to 10 seconds, especially in
very cold weather (below −18°C
or 0°F), it could be flooded with
too much gasoline. Try pushing
the accelerator pedal all the way to the floor and holding it there
as you press the ENGINE
START/STOP button, for up to a
maximum of 15 seconds. Wait at
least 15 seconds between each
try, to allow the cranking motor
to cool down. When the engine
starts, let go of the button, and
the accelerator. If the vehicle
starts briefly but then stops
again, do the same thing. This
clears the extra gasoline from
the engine. Do not race the
engine immediately after starting
it. Operate the engine and
transmission gently until the oil
warms up and lubricates all
moving parts.
eAssist Automatic Engine
Start/Stop
{Warning
Exiting the vehicle without first
shifting into P (Park) may cause
the vehicle to move. You or others
(Continued)
Warning (Continued)
may be injured. Because the
vehicle has the automatic engine
start/stop feature, the vehicle's
engine might seem to be shut off;
however, once the brake pedal is
released, the engine will start up
again.
Shift to P (Park) and turn the
ignition to LOCK/OFF, before
exiting the vehicle.
Vehicles with eAssist have an
automatic engine start/stop feature.
After the engine is started and has
reached operating temperature, the
auto stop feature may cause the
engine to turn off when the brakes
are applied and the vehicle comes
to a complete stop. The vehicle may
remain in auto stop for up to
two minutes. When the brake is
released or the accelerator pedal
applied, the engine will start. The
engine will continue to run until the
next auto stop.

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 (27,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Driving and Operating 9-27
Automatic
Transmission
Shift Lever without Selective RideControl Shown
P (Park): This position locks the
front wheels. It is the best position
to use when starting the engine
because the vehicle cannot move
easily.
{Warning
It is dangerous to get out of the
vehicle if the shift lever is not fully
in P (Park) with the parking brake
firmly set. The vehicle can roll.
Do not leave the vehicle when the
engine is running. If you have left
the engine running, the vehicle
can move suddenly. You or others
could be injured. To be sure the
vehicle will not move, even when
you are on fairly level ground,
always set the parking brake and
move the shift lever to P (Park).
See Shifting Into Park on
page 9-24 andDriving
Characteristics and Towing Tips
on page 9-63.
Make sure the shift lever is fully in
P (Park) before starting the engine.
The vehicle has an automatic
transmission shift lock control
system. The regular brake must be
fully applied first and then the shift lever button pressed before shifting
from P (Park) when the ignition key
is in ON/RUN. If you cannot shift out
of P (Park), ease pressure on the
shift lever, then push the shift lever
all the way into P (Park) as you
maintain brake application. Then
press the shift lever button and
move the shift lever into another
gear. See
Shifting out of Park on
page 9-25.
R (Reverse): Use this gear to
back up.
{Caution
Shifting to R (Reverse) while the
vehicle is moving forward could
damage the transmission. The
repairs would not be covered by
the vehicle warranty. Shift to
R (Reverse) only after the vehicle
is stopped.

Black plate (3,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Vehicle Care 10-3
California Proposition
65 Warning
Most motor vehicles, including this
one, contain and/or emit chemicals
known to the State of California to
cause cancer and birth defects or
other reproductive harm. Engine
exhaust, many parts and systems,
many fluids, and some component
wear by-products contain and/or
emit these chemicals.
California Perchlorate
Materials Requirements
Certain types of automotive
applications, such as airbag
initiators, safety belt pretensioners,
and lithium batteries contained in
Remote Keyless Entry transmitters,
may contain perchlorate materials.
Special handling may be necessary.For additional information, see
www.dtsc.ca.gov/hazardouswaste/
perchlorate.
Accessories and
Modifications
Adding non‐dealer accessories or
making modifications to the vehicle
can affect vehicle performance and
safety, including such things as
airbags, braking, stability, ride and
handling, emissions systems,
aerodynamics, durability, and
electronic systems like antilock
brakes, traction control, and stability
control. These accessories or
modifications could even cause
malfunction or damage not covered
by the vehicle warranty.
Damage to vehicle components
resulting from modifications or the
installation or use of non‐GM
certified parts, including control
module or software modifications, is
not covered under the terms of the
vehicle warranty and may affect
remaining warranty coverage for
affected parts.
GM Accessories are designed to
complement and function with other
systems on the vehicle. See your
dealer to accessorize the vehicle
using genuine GM Accessories
installed by a dealer technician.
Also, see
Adding Equipment to the
Airbag-Equipped Vehicle on
page 3-31.

Black plate (29,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Vehicle Care 10-29
Automatic Transmission
Shift Lock Control
Function Check
{Warning
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle. It should be
parked on a level surface.
2. Apply the parking brake. Be ready to apply the regular brake
immediately if the vehicle begins
to move. 3. With the engine off, turn the
ignition on, but do not start the
engine. Without applying the
regular brake, try to move the
shift lever out of P (Park) with
normal effort. If the shift lever
moves out of P (Park), contact
your dealer for service.
Ignition Transmission
Lock Check
If equipped with a key type ignition,
while parked and with the parking
brake set, try to turn the ignition to
LOCK/OFF in each shift lever
position.
.The ignition should turn to
LOCK/OFF only when the shift
lever is in P (Park).
.The ignition key should come
out only in LOCK/OFF.
Contact your dealer if service is
required.
Park Brake and P (Park)
Mechanism Check
{Warning
When you are doing this check,
the vehicle could begin to move.
You or others could be injured
and property could be damaged.
Make sure there is room in front
of the vehicle in case it begins to
roll. Be ready to apply the regular
brake at once should the vehicle
begin to move.
Park on a fairly steep hill, with the
vehicle facing downhill. Keeping
your foot on the regular brake, set
the parking brake.
.To check the parking brake's
holding ability: With the engine
running and the transmission in
N (Neutral), slowly remove foot
pressure from the regular brake
pedal. Do this until the vehicle is
held by the parking brake only.