ECU BUICK LACROSSE 2015 Owner's Manual

Black plate (1,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
2015 Buick LaCrosse Owner ManualM
In Brief. . . . . . . . . . . . . . . . . . . . . . . . 1-1
Instrument Panel . . . . . . . . . . . . . . 1-2
Initial Drive Information . . . . . . . . 1-4
Vehicle Features . . . . . . . . . . . . . 1-15
eAssist Features . . . . . . . . . . . . . 1-19
Performance and
Maintenance . . . . . . . . . . . . . . . . 1-21
Keys, Doors, and Windows . . . . . . . . . . . . . . . . . . . . 2-1
Keys and Locks . . . . . . . . . . . . . . . 2-1
Doors . . . . . . . . . . . . . . . . . . . . . . . . 2-13
Vehicle Security . . . . . . . . . . . . . . 2-15
Exterior Mirrors . . . . . . . . . . . . . . . 2-18
Interior Mirrors . . . . . . . . . . . . . . . . 2-19
Windows . . . . . . . . . . . . . . . . . . . . . 2-20
Roof . . . . . . . . . . . . . . . . . . . . . . . . . . 2-23
Seats and Restraints . . . . . . . . . 3-1
Head Restraints . . . . . . . . . . . . . . . 3-2
Front Seats . . . . . . . . . . . . . . . . . . . . 3-4
Rear Seats . . . . . . . . . . . . . . . . . . . 3-11
Safety Belts . . . . . . . . . . . . . . . . . . 3-12
Airbag System . . . . . . . . . . . . . . . . 3-20
Child Restraints . . . . . . . . . . . . . . 3-33 Storage
. . . . . . . . . . . . . . . . . . . . . . . 4-1
Storage Compartments . . . . . . . . 4-1
Additional Storage Features . . . 4-3
Instruments and Controls . . . . 5-1
Controls . . . . . . . . . . . . . . . . . . . . . . . 5-2
Warning Lights, Gauges, and
Indicators . . . . . . . . . . . . . . . . . . . . 5-7
Information Displays . . . . . . . . . . 5-26
Vehicle Messages . . . . . . . . . . . . 5-35
Vehicle Personalization . . . . . . . 5-45
Universal Remote System . . . . 5-51
Lighting . . . . . . . . . . . . . . . . . . . . . . . 6-1
Exterior Lighting . . . . . . . . . . . . . . . 6-1
Interior Lighting . . . . . . . . . . . . . . . . 6-5
Lighting Features . . . . . . . . . . . . . . 6-6
Infotainment System . . . . . . . . . 7-1
Introduction . . . . . . . . . . . . . . . . . . . . 7-1 Climate Controls
. . . . . . . . . . . . . 8-1
Climate Control Systems . . . . . . 8-1
Air Vents . . . . . . . . . . . . . . . . . . . . . . . 8-6
Maintenance . . . . . . . . . . . . . . . . . . . 8-6
Driving and Operating . . . . . . . . 9-1
Driving Information . . . . . . . . . . . . . 9-2
Starting and Operating . . . . . . . 9-14
Engine Exhaust . . . . . . . . . . . . . . 9-26
Automatic Transmission . . . . . . 9-27
Drive Systems . . . . . . . . . . . . . . . . 9-30
Brakes . . . . . . . . . . . . . . . . . . . . . . . 9-30
Ride Control Systems . . . . . . . . 9-34
Cruise Control . . . . . . . . . . . . . . . . 9-37
Driver Assistance Systems . . . 9-47
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 9-58
Trailer Towing . . . . . . . . . . . . . . . . 9-63
Conversions and Add-Ons . . . 9-68

Black plate (18,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
1-18 In Brief
Universal Remote System
If equipped, these buttons in the
overhead console provide a way to
replace up to three remote control
transmitters used to activate
devices such as garage door
openers, security systems, and
home automation devices.
Read the instructions completely
before attempting to program the
Universal Remote system. Because
of the steps involved, it may behelpful to have another person
available to assist with programming
the Universal Remote system.
See
Universal Remote System on
page 5-51.
Sunroof
On vehicles with a sunroof, the
switches are located on the
overhead console. The ignition must be in ON/RUN or
ACC/ACCESSORY, or Retained
Accessory Power (RAP) must be
active. See
Retained Accessory
Power (RAP) on page 9-23.
Vent: Press the rear of the
switch (2) to the first detent to vent
the sunroof. Press the front of the
switch (1) to the second detent to
close the sunroof.
Express-open/Express-close: To
express-open the sunroof, fully
press and release the rear of the
switch (2). To express-close, fully
press and release the front of the
switch (1). To stop the sunroof
partway, press either switch a
second time.
The sunshade opens automatically
with the sunroof.

Black plate (23,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
In Brief 1-23
E85 or FlexFuel
Vehicles with a yellow fuel cap can
use either unleaded gasoline or
ethanol fuel containing up to 85%
ethanol (E85). SeeE85 or FlexFuel
on page 9-60. For all other vehicles,
use only the unleaded gasoline
described under Fuel on page 9-58.
Driving for Better Fuel
Economy
Driving habits can affect fuel
mileage. Here are some driving tips
to get the best fuel economy
possible.
.Avoid fast starts and accelerate
smoothly.
.Brake gradually and avoid
abrupt stops.
.Avoid idling the engine for long
periods of time.
.When road and weather
conditions are appropriate, use
cruise control.
.Always follow posted speed
limits or drive more slowly when
conditions require.
.Keep vehicle tires properly
inflated.
.Combine several trips into a
single trip.
.Replace the vehicle's tires with
the same TPC Spec number
molded into the tire's sidewall
near the size.
.Follow recommended scheduled
maintenance.
Roadside Assistance
Program
U.S.: 1-800-252-1112
TTY Users (U.S. Only):
1-888-889-2438
Canada: 1-800-268-6800
New Buick owners are automatically
enrolled in the Roadside Assistance
Program. See
Roadside Assistance Program
on page 13-5.
OnStar®
This vehicle may be equipped with a
comprehensive, in-vehicle system
that can connect to a live OnStar
Advisor for Emergency, Security,
Navigation, Connection, and
Diagnostic Services. OnStar
services may require a paid
subscription. See OnStar Overview
on page 14-1.

Black plate (1,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Keys, Doors, and Windows 2-1
Keys, Doors, and
Windows
Keys and Locks
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Remote Keyless Entry (RKE)System . . . . . . . . . . . . . . . . . . . . . . 2-2
Remote Keyless Entry (RKE) System Operation . . . . . . . . . . . 2-3
Remote Vehicle Start . . . . . . . . . 2-9
Door Locks . . . . . . . . . . . . . . . . . . 2-11
Power Door Locks . . . . . . . . . . . 2-11
Delayed Locking . . . . . . . . . . . . . 2-12
Automatic Door Locks . . . . . . . 2-12
Lockout Protection . . . . . . . . . . . 2-12
Safety Locks . . . . . . . . . . . . . . . . . 2-12
Doors
Trunk . . . . . . . . . . . . . . . . . . . . . . . . 2-13
Vehicle Security
Vehicle Security . . . . . . . . . . . . . . 2-15
Vehicle Alarm System . . . . . . . 2-15 Immobilizer . . . . . . . . . . . . . . . . . . 2-16
Immobilizer Operation (Key
Access) . . . . . . . . . . . . . . . . . . . . 2-16
Immobilizer Operation (Keyless Access) . . . . . . . . . . . 2-17
Exterior Mirrors
Convex Mirrors . . . . . . . . . . . . . . 2-18
Power Mirrors . . . . . . . . . . . . . . . . 2-18
Folding Mirrors . . . . . . . . . . . . . . . 2-19
Heated Mirrors . . . . . . . . . . . . . . . 2-19
Reverse Tilt Mirrors . . . . . . . . . . 2-19
Interior Mirrors
Interior Rearview Mirrors . . . . . 2-19
Manual Rearview Mirror . . . . . . 2-20
Automatic Dimming Rearview
Mirror . . . . . . . . . . . . . . . . . . . . . . . 2-20
Windows
Windows . . . . . . . . . . . . . . . . . . . . . 2-20
Power Windows . . . . . . . . . . . . . 2-20
Sun Visors . . . . . . . . . . . . . . . . . . . 2-22
Rear Window Sunshade . . . . . 2-22
Roof
Sunroof . . . . . . . . . . . . . . . . . . . . . . 2-23
Keys and Locks
Keys
{Warning
Leaving children in a vehicle with
an ignition key or Remote
Keyless Entry (RKE) transmitter is
dangerous and children or others
could be seriously injured or
killed. They could operate the
power window or other controls or
make the vehicle move. The
windows will function with the key
in the ignition or with the RKE
transmitter in the vehicle, and
children or others could be caught
in the path of a closing window.
Do not leave children in a vehicle
with the ignition key or an RKE
transmitter.

Black plate (5,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Keys, Doors, and Windows 2-5
Passive Locking
If equipped with Keyless Access,
the vehicle will lock several seconds
after all doors are closed if the
vehicle is off and at least one
transmitter has been removed or
none remain in the interior.
If other electronic devices interfere
with the RKE transmitter signal, the
vehicle may not detect the RKE
transmitter inside the vehicle.
If passive locking is enabled, the
doors may lock with the RKE
transmitter inside the vehicle. Do
not leave the RKE transmitter in an
unattended vehicle.
Temporary Disable Passive
Locking Feature
Temporarily disable the passive
locking by pressing and holding
K
on the interior door switch with a
door open for at least four seconds,
or until three chimes are heard.
Passive locking will then remaindisabled until
Qon the interior door
is pressed, or until the vehicle is
turned on.
To customize the doors to
automatically lock when exiting the
vehicle, see “Remote Lock, Unlock,
Start” under Vehicle Personalization
on page 5-45.
Keyless Trunk Opening
Lift up on the touch pad above the
license plate to open the trunk if the
RKE transmitter is within 1 m (3 ft).
Programming Transmitters to
the Vehicle
Only RKE transmitters programmed
to the vehicle will work. If a
transmitter is lost or stolen, a
replacement can be purchased and
programmed through your dealer.
The vehicle can be reprogrammed
so that lost or stolen transmitters no
longer work. Any remaining
transmitters will need to be
reprogrammed. Each vehicle can
have up to eight transmitters
matched to it. Programming with a Recognized
Transmitter (Key Vehicles Only)
To program a new key:
1. Insert the original, already
programmed key in the ignition
and turn to the key to the ON/
RUN position.
2. Turn the key to LOCK/OFF and remove the key.
3. Insert the new key to be programmed and turn it to the
ON/RUN position within
five seconds.
The security light will turn off
once the key has been
programmed.
4. Repeat Steps 1–3 if additional keys are to be programmed.
If a key is lost or damaged, see your
dealer to have a new key made.

Black plate (6,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
2-6 Keys, Doors, and Windows
Programming without a
Recognized Transmitter (Key
Vehicles Only)
Program a new key to the vehicle
when a recognized key is not
available. Canadian regulations
require that owners see their
dealer.
If there are no currently recognized
keys available, follow this procedure
to program the first key.
This procedure will take
approximately 30 minutes to
complete for the first key. The
vehicle must be off and all of the
keys you wish to program must be
with you.
1. Insert the new vehicle key intothe ignition.
2. Turn to ON/RUN. The security light will come on.
3. Wait 10 minutes until the security light turns off.
4. Turn the ignition to LOCK/OFF. 5. Repeat Steps 2–4 two more
times. After the third time, turn to
ON/RUN; the key is learned and
all previously known keys will no
longer work with the vehicle.
Remaining keys can be learned by
following the procedure in
“Programming with a Recognized
Transmitter (Key Vehicles Only).”
Programming with a Recognized
Transmitter (Keyless Access
Vehicles Only)
A new transmitter can be
programmed to the vehicle when
there is one recognized transmitter.
To program, the vehicle must be off
and all of the transmitters, both
currently recognized and new, must
be with you.
1. Place the recognized transmitter(s) in the cupholder. 2. Insert the vehicle key of the new
transmitter into the key lock
cylinder on the outside of the
driver door and turn the key to
the unlock position five times
within 10 seconds.
The Driver Information Center
(DIC) displays READY FOR
REMOTE #2, 3, 4 or 5.
3. Place the new transmitter into
the transmitter pocket inside the
armrest storage area.

Black plate (14,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
2-14 Keys, Doors, and Windows
Warning (Continued)
.Adjust the climate control
system to a setting that
brings in only outside air and
set the fan speed to the
highest setting. See“Climate
Control Systems” in the
Index.
.If the vehicle has a power
liftgate, disable the power
liftgate function.
For more information about
carbon monoxide, see Engine
Exhaust on page 9-26.
Remote Trunk Release
To open the trunk, pressVon the
driver door when the vehicle is off or
in P (Park).
To open the trunk from outside the
vehicle, press and hold
Yon the
Remote Keyless Entry (RKE)
transmitter to unlock all doors, then
use the touch pad above the license
plate. If equipped with Keyless
Access, the trunk can be opened
using the touch pad when the RKE
transmitter is within 1 m (3 ft) of the
rear of the vehicle.
Emergency Trunk Release
Handle
{Caution
Do not use the emergency trunk
release handle as a tie-down or
anchor point when securing items
in the trunk as it could damage
the handle.

Black plate (15,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Keys, Doors, and Windows 2-15
There is an emergency trunk
release handle located inside the
trunk on the trunk latch. On some
vehicles, the release handle can be
accessed by folding the rear seat
center seatback. SeeRear Seats on
page 3-11. Pull the release handle
to open the trunk from the inside.
After use, return to the stored
position.
Vehicle Security
This vehicle has theft-deterrent
features; however, they do not make
the vehicle impossible to steal.
Vehicle Alarm System
This vehicle has an anti-theft alarm
system.
The indicator light, on the
instrument panel near the
windshield, indicates the status of
the system.
Off: Alarm system is disarmed. On Solid:
Vehicle is secured
during the delay to arm the system.
Fast Flash: Vehicle is unsecured.
A door, the hood, or the trunk
is open.
Slow Flash: Alarm system is
armed.
Arming the Alarm System
1. Turn off the vehicle.
2. Lock the vehicle in one of three ways:
.Use the RKE transmitter.
.Use the Keyless Access
system, if equipped.
.With a door open, pressQ
on the interior of the door.
3. After 30 seconds the alarm system will arm, and the
indicator light will begin to slowly
flash indicating the alarm system
is operating. Pressing
Qon the
RKE transmitter a second time

Black plate (16,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
2-16 Keys, Doors, and Windows
will bypass the 30-second delay
and immediately arm the alarm
system.
The vehicle alarm system will not
arm if the doors are locked with
the key.
If the driver door is opened without
first unlocking the RKE transmitter,
the horn will chirp and the lights will
flash to indicate pre-alarm. If the
vehicle is not started, or the door is
not unlocked by pressing
Kon the
RKE transmitter during the
10-second pre-alarm, the alarm will
be activated.
The alarm will also be activated if a
passenger door, the trunk, or the
hood is opened without first
disarming the system. When the
alarm is activated, the turn signals
flash and the horn sounds for about
30 seconds. The alarm system will
then re-arm to monitor for the next
unauthorized event.
Disarming the Alarm System
To disarm the alarm system, or turn
off the alarm if it has been activated,
do one of the following:
.PressKon the RKE transmitter.
.Unlock the vehicle using the
Keyless Access system,
if equipped.
.Start the vehicle.
To avoid setting off the alarm by
accident:
.Lock the vehicle after all
occupants have left the vehicle
and all doors are closed.
.Always unlock a door with the
RKE transmitter or use the
Keyless Access system.
Unlocking the driver door with the
key will not disarm the alarm system
or turn off the alarm.
How to Detect a Tamper
Condition
IfKis pressed on the transmitter
and the horn chirps and the lights
flash three times, the alarm was
activated while the system was
armed.
If the alarm has been activated, a
message will appear on the DIC.
See Security Messages on
page 5-43.
Immobilizer
See Radio Frequency Statement on
page 13-12.
Immobilizer Operation
(Key Access)
This vehicle has a passive
theft-deterrent system.
The system does not have to be
manually armed or disarmed.
The vehicle is automatically
immobilized when the key is
removed from the ignition.

Black plate (17,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Keys, Doors, and Windows 2-17
The system is automatically
disarmed when the vehicle is
started with the correct key. The key
uses a transponder that matches an
immobilizer control unit in the
vehicle and automatically disarms
the system. Only the correct key
starts the vehicle. The vehicle may
not start if the key is damaged.
The security light in the instrument
cluster comes on if there is a
problem with arming or disarming
the theft-deterrent system.
When trying to start the vehicle, the
security light comes on briefly when
the ignition is turned on.
If the engine does not start and the
security light stays on, there is a
problem with the system. Turn the
ignition off and try again.If the engine still does not start, and
the key appears to be undamaged
or the light continues to stay on, try
another ignition key.
If the engine still does not start with
the other key, the vehicle needs
service. If the vehicle does start, the
first key may be damaged. See your
dealer who can service the
theft-deterrent system and have a
new key made.
Do not leave the key or device that
disarms or deactivates the
theft-deterrent system in the vehicle.Immobilizer Operation
(Keyless Access)
This vehicle has a passive
theft-deterrent system.
The system does not have to be
manually armed or disarmed.
The vehicle is automatically
immobilized when the transmitter
leaves the vehicle.
The immobilization system is
disarmed when the ignition button is
pushed in and a valid transmitter is
found in the vehicle.
The security light on the instrument
cluster comes on when there is a
problem with arming or disarming
the theft-deterrent system.
The system has one or more
transmitters matched to an
immobilizer control unit in the
vehicle. Only a correctly matched
transmitter will start the vehicle.
If the transmitter is ever damaged,
you may not be able to start your
vehicle.
When trying to start the vehicle, the
security light comes on briefly when
the ignition is turned on.