2015 BUICK LACROSSE ECU

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.

Black plate (18,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
2-18 Keys, Doors, and Windows
If the vehicle does not start and the
security light stays on, there is a
problem with the system. Turn the
vehicle off and try again.
If the RKE transmitter appears to be
undamaged, try another transmitter,
or place the transmitter in the
transmitter pocket. See“Starting the
Vehicle with a Low Transmitter
Battery” underRemote Keyless
Entry (RKE) System Operation on
page 2-3.
If the vehicle does not start with the
other transmitter or when the
transmitter is in the transmitter
pocket, your vehicle needs service.
See your dealer who can service
the theft-deterrent system and have
a new transmitter programmed to
the vehicle.
Do not leave the transmitter or
device that disarms or deactivates
the theft-deterrent system in the
vehicle.Exterior Mirrors
Convex Mirrors
{Warning
A convex mirror can make things,
like other vehicles, look farther
away than they really are. If you
cut too sharply into the right lane,
you could hit a vehicle on the
right. Check the inside mirror or
glance over your shoulder before
changing lanes.
The passenger side mirror is convex
shaped. A convex mirror's surface is
curved so more can be seen from
the driver seat.
Power Mirrors
To adjust the mirrors:
1. Turn the control knob to the L (Left) or R (Right) selecting the
driver or passenger mirror.
2. Push the control knob to the left, right, up, or down to adjust the
mirror.
Vehicles with the memory feature
can store a preferred mirror position.
See Memory Seats on page 3-7.

Black plate (1,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Seats and Restraints 3-1
Seats and
Restraints
Head Restraints
Head Restraints . . . . . . . . . . . . . . . 3-2
Front Seats
Seat Adjustment . . . . . . . . . . . . . . 3-4
Power Seat Adjustment . . . . . . . 3-5
Lumbar Adjustment . . . . . . . . . . . 3-5
Reclining Seatbacks . . . . . . . . . . 3-6
Memory Seats . . . . . . . . . . . . . . . . 3-7
Heated and Ventilated FrontSeats . . . . . . . . . . . . . . . . . . . . . . . . 3-9
Rear Seats
Rear Seats . . . . . . . . . . . . . . . . . . 3-11
Rear Seat Armrest . . . . . . . . . . . 3-12
Safety Belts
Safety Belts . . . . . . . . . . . . . . . . . . 3-12
How to Wear Safety BeltsProperly . . . . . . . . . . . . . . . . . . . . 3-14 Lap-Shoulder Belt . . . . . . . . . . . 3-15
Safety Belt Use During
Pregnancy . . . . . . . . . . . . . . . . . . 3-18
Safety Belt Extender . . . . . . . . . 3-19
Safety System Check . . . . . . . . 3-19
Safety Belt Care . . . . . . . . . . . . . 3-19
Replacing Safety Belt System Parts after a Crash . . . . . . . . . 3-20
Airbag System
Airbag System . . . . . . . . . . . . . . . 3-20
Where Are the Airbags? . . . . . 3-22
When Should an AirbagInflate? . . . . . . . . . . . . . . . . . . . . . 3-23
What Makes an Airbag Inflate? . . . . . . . . . . . . . . . . . . . . . 3-24
How Does an Airbag
Restrain? . . . . . . . . . . . . . . . . . . . 3-24
What Will You See after an Airbag Inflates? . . . . . . . . . . . . 3-25
Passenger Sensing System . . . . . . . . . . . . . . . . . . . . . 3-26
Servicing the Airbag-Equipped Vehicle . . . . . . . . . . . . . . . . . . . . . 3-31 Adding Equipment to the
Airbag-Equipped Vehicle . . . 3-31
Airbag System Check . . . . . . . . 3-32
Replacing Airbag System Parts after a Crash . . . . . . . . . 3-32
Child Restraints
Older Children . . . . . . . . . . . . . . . 3-33
Infants and Young
Children . . . . . . . . . . . . . . . . . . . . 3-35
Child Restraint Systems . . . . . 3-38
Where to Put the Restraint . . . 3-39
Lower Anchors and Tethers for Children (LATCH
System) . . . . . . . . . . . . . . . . . . . . 3-41
Replacing LATCH System Parts After a Crash . . . . . . . . . 3-48
Securing Child Restraints (Rear Seat) . . . . . . . . . . . . . . . . . 3-49
Securing Child Restraints (Front Passenger Seat) . . . . 3-51

Black plate (4,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
3-4 Seats and Restraints
The head restraint will fold rearward
automatically.
When an occupant or child restraint
is in the seat, always return the
head restraint to the full upright
position. Lift the head restraint and
pull it forward until it locks into
place. Push and pull on the head
restraint to make sure that it is
locked.Always adjust the head restraint so
that the top of the restraint is at the
same height as the top of the
occupant’s head.
If you are installing a child restraint
in the rear seat, see
“Securing a
Child Restraint Designed for the
LATCH System” underLower
Anchors and Tethers for Children
(LATCH System) on page 3-41.
Front Seats
Seat Adjustment
Seat Position
{Warning
You can lose control of the
vehicle if you try to adjust a driver
seat while the vehicle is moving.
Adjust the driver seat only when
the vehicle is not moving.

Black plate (15,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Seats and Restraints 3-15
Lap-Shoulder Belt
All seating positions in the vehicle
have a lap-shoulder belt.
The following instructions explain
how to wear a lap-shoulder belt
properly.
1. Adjust the seat, if the seat isadjustable, so you can sit up
straight. To see how, see “Seats”
in the Index.
2. Pick up the latch plate and pull the belt across you. Do not let it
get twisted.
The lap-shoulder belt may lock if
you pull the belt across you very
quickly. If this happens, let the
belt go back slightly to unlock it.
Then pull the belt across you
more slowly.
If the shoulder portion of a
passenger belt is pulled out all
the way, the child restraint
locking feature may be engaged.
If this happens, let the belt go
back all the way and start again.
3. Push the latch plate into the
buckle until it clicks.
Pull up on the latch plate to
make sure it is secure. If the belt
is not long enough, see Safety
Belt Extender on page 3-19.
Position the release button on
the buckle so that the safety belt
could be quickly unbuckled if
necessary.
If equipped with a shoulder belt
height adjuster, move it to the
height that is right for you. See
“Shoulder Belt Height Adjuster”

Black plate (19,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Seats and Restraints 3-19
A pregnant woman should wear a
lap-shoulder belt, and the lap
portion should be worn as low as
possible, below the rounding,
throughout the pregnancy.
The best way to protect the fetus is
to protect the mother. When a safety
belt is worn properly, it is more likely
that the fetus will not be hurt in a
crash. For pregnant women, as for
anyone, the key to making safety
belts effective is wearing them
properly.
Safety Belt Extender
If the vehicle's safety belt will fasten
around you, you should use it.
But if a safety belt is not long
enough, your dealer will order you
an extender. When you go in to
order it, take the heaviest coat you
will wear, so the extender will be
long enough for you. To help avoidpersonal injury, do not let someone
else use it, and use it only for the
seat it is made to fit. The extender
has been designed for adults. Never
use it for securing child seats. To
wear it, attach it to the regular safety
belt. See the instruction sheet that
comes with the extender.
Safety System Check
Now and then, check that the safety
belt reminder light, safety belts,
buckles, latch plates, retractors, and
anchorages are all working properly.
Look for any other loose or
damaged safety belt system parts
that might keep a safety belt system
from doing its job. See your dealer
to have it repaired. Torn or frayed
safety belts may not protect you in a
crash. They can rip apart under
impact forces. If a belt is torn or
frayed, get a new one right away.
Make sure the safety belt reminder
light is working. See
Safety Belt
Reminders on page 5-14.
Keep safety belts clean and dry.
See Safety Belt Care on page 3-19.
Safety Belt Care
Keep belts clean and dry.
{Warning
Do not bleach or dye safety belts.
It may severely weaken them. In
a crash, they might not be able to
provide adequate protection.
Clean safety belts only with mild
soap and lukewarm water.

Black plate (22,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
3-22 Seats and Restraints
{Warning
Children who are up against,
or very close to, any airbag when
it inflates can be seriously injured
or killed. Always secure children
properly in the vehicle. To read
how, seeOlder Children on
page 3-33 orInfants and Young
Children on page 3-35.
There is an airbag readiness light
on the instrument cluster, which
shows the airbag symbol. The
system checks the airbag electrical
system for malfunctions. The light
tells you if there is an electrical
problem. See Airbag Readiness
Light on page 5-14.
Where Are the Airbags?
The driver frontal airbag is in the
center of the steering wheel.
The front outboard passenger
frontal airbag is in the passenger
side instrument panel.
Driver Side Shown, Passenger
Side Similar
The driver and front outboard
passenger seat-mounted side
impact airbags are in the side of the
seatbacks closest to the door.
The roof-rail airbags for the driver,
front outboard passenger, and
second row outboard passengers
are in the ceiling above the side
windows.