2019 BUICK LACROSSE ECU

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
22 In Brief
The vehicle has three power outlets:
.Under the front of the center
console
. Inside the center console
storage
. On the rear of the center
console
Open the protective cover to use the
power outlet.
The outlet is powered when the
ignition is on or in ACC/
ACCESSORY, or until the driver
door is opened within 10 minutes of
turning off the vehicle. See Retained
Accessory Power (RAP) 0181.
See Power Outlets 0108.Universal Remote System
If equipped, this system provides 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 be
helpful to have another person
available to assist with programming
the Universal Remote system. See
Universal Remote System
0 145.
Sunroof
1. Sunroof Switch
2. Power Sunshade
Switch (Rear)
3. Power Sunshade Switch (Sunroof)
On vehicles with a sunroof, the
switches are on the overhead
console.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
28 Keys, Doors, and Windows
Keys, Doors, and
Windows
Keys and Locks
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Remote Keyless Entry (RKE)System . . . . . . . . . . . . . . . . . . . . . . . 29
Remote Keyless Entry (RKE) System Operation . . . . . . . . . . . . 29
Remote Vehicle Start . . . . . . . . . . 35
Door Locks . . . . . . . . . . . . . . . . . . . . 37
Power Door Locks . . . . . . . . . . . . . 39
Delayed Locking . . . . . . . . . . . . . . . 39
Automatic Door Locks . . . . . . . . . 39
Lockout Protection . . . . . . . . . . . . . 40
Safety Locks . . . . . . . . . . . . . . . . . . . 40
Doors
Trunk . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Vehicle Security
Vehicle Security . . . . . . . . . . . . . . . . 43
Vehicle Alarm System . . . . . . . . . 43
Immobilizer . . . . . . . . . . . . . . . . . . . . 44
Immobilizer Operation . . . . . . . . . 44
Exterior Mirrors
Convex Mirrors . . . . . . . . . . . . . . . . 45
Power Mirrors . . . . . . . . . . . . . . . . . . 45 Folding Mirrors . . . . . . . . . . . . . . . . . 46
Heated Mirrors . . . . . . . . . . . . . . . . . 46
Automatic Dimming Mirror . . . . . 46
Reverse Tilt Mirrors . . . . . . . . . . . . 46
Interior Mirrors
Interior Rearview Mirrors . . . . . . . 47
Automatic Dimming Rearview
Mirror . . . . . . . . . . . . . . . . . . . . . . . . . 47
Windows
Windows . . . . . . . . . . . . . . . . . . . . . . . 47
Power Windows . . . . . . . . . . . . . . . 47
Sun Visors . . . . . . . . . . . . . . . . . . . . . 49
Rear Window Sunshade . . . . . . . 50
Roof
Sunroof . . . . . . . . . . . . . . . . . . . . . . . . 50
Keys and Locks
Keys
{Warning
Leaving children in a vehicle with
a Remote Keyless Entry (RKE)
transmitter is dangerous and
children or others could be
seriously injured or killed. They
could operate the power windows
or other controls or make the
vehicle move. The windows will
function 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 an RKE
transmitter.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
Keys, Doors, and Windows 39
1. Position the bottom edge of thecap under the lower edge of
the metal piece (2). The
tabs (3) attach to the metal
piece (2) at the positions (1)
2. Rotate the cap upward and install into place.
3. Check that the cap is secure.
Free-Turning Locks
The door key lock cylinder turns
freely when either the wrong key is
used, or the correct key is not fully
inserted. The free-turning door lock
feature prevents the lock from being
forced open. To reset the lock, turn
it to the vertical position with the
correct key fully inserted. Remove
the key and insert it again. If this
does not reset the lock, turn the key
halfway around in the cylinder and
repeat the reset procedure.
Power Door Locks
K: Press to unlock the doors.
Q: Press to lock the doors.
The indicator light in the switch will
illuminate when activated.
Delayed Locking
This feature delays the locking of
the doors until five seconds after all
doors are closed.
Delayed locking can only be turned
on when the Unlocked Door
Anti-Lockout has been turned off. When
Qis pressed on the power
door lock switch while the door is
open, a chime will sound three
times indicating delayed locking is
active.
The doors will lock automatically
five seconds after all doors are
closed. If a door is reopened before
that time, the five-second timer will
reset when all doors are closed
again.
Press
Qon the door lock switch
again or press
Qon the RKE
transmitter to lock the doors
immediately.
This feature can also be
programmed. See Vehicle
Personalization 0138.
Automatic Door Locks
The doors will lock automatically
when all doors are closed, the
ignition is on, and the vehicle is
shifted out of P (Park).

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
42 Keys, Doors, and Windows
.To open the trunk, press|on
the driver door when the vehicle
is off or in P (Park).
. To open the trunk from outside
the vehicle, press
Xtwice
quickly on the Remote Keyless
Entry (RKE) transmitter.
. Press the bottom of the emblem
above the license plate when all
doors are unlocked or when the
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.
There is a glow-in-the-dark
emergency trunk release handle on
the trunk lid. This handle will glow following exposure to light. Pull the
release handle to open the trunk
from the inside.
After pulling the emergency trunk
release handle, push the handle
back into the bezel.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
Keys, Doors, and Windows 43
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.
. With a door open, press
Q
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 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 with 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.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
44 Keys, Doors, and Windows
Disarming the Alarm System
To disarm the alarm system or turn
off the alarm if it has been activated,
do one of the following:
.Press
Kon the RKE transmitter.
. Unlock the vehicle using the
Keyless Access system.
. 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 Driver
Information Center (DIC).
Immobilizer
See Radio Frequency Statement
0 345.
Immobilizer Operation
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
pressed 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 the
vehicle.
When trying to start the vehicle, the
security light comes on briefly when
the ignition is turned on.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
Keys, Doors, and Windows 45
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 029.
If the vehicle does not start with the
other transmitter or when the
transmitter is in the transmitter
pocket, the 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. Press
}or|to select the
driver or passenger mirror.
2. Press the control button below (left, right, up, or down) to
adjust the mirror.
Vehicles with the memory feature
can store a preferred mirror position.
See Memory Seats 056.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
52 Seats and Restraints
Seats and
Restraints
Head Restraints
Head Restraints . . . . . . . . . . . . . . . 53
Front Seats
Power Seat Adjustment . . . . . . . . 54
Lumbar Adjustment . . . . . . . . . . . . 55
Reclining Seatbacks . . . . . . . . . . . 55
Memory Seats . . . . . . . . . . . . . . . . . 56
Heated and Ventilated FrontSeats . . . . . . . . . . . . . . . . . . . . . . . . . 59
Massage . . . . . . . . . . . . . . . . . . . . . . . 60
Rear Seats
Rear Seats . . . . . . . . . . . . . . . . . . . . 61
Rear Seat Armrest . . . . . . . . . . . . . 63
Seat Belts
Seat Belts . . . . . . . . . . . . . . . . . . . . . 63
How to Wear Seat Belts Properly . . . . . . . . . . . . . . . . . . . . . . 64
Lap-Shoulder Belt . . . . . . . . . . . . . 66
Seat Belt Use During Pregnancy . . . . . . . . . . . . . . . . . . . . 69
Seat Belt Extender . . . . . . . . . . . . . 69
Safety System Check . . . . . . . . . . 69
Seat Belt Care . . . . . . . . . . . . . . . . . 70 Replacing Seat Belt System
Parts after a Crash . . . . . . . . . . . 70
Airbag System
Airbag System . . . . . . . . . . . . . . . . . 71
Where Are the Airbags? . . . . . . . 72
When Should an AirbagInflate? . . . . . . . . . . . . . . . . . . . . . . . 74
What Makes an Airbag Inflate? . . . . . . . . . . . . . . . . . . . . . . . 75
How Does an Airbag Restrain? . . . . . . . . . . . . . . . . . . . . . 75
What Will You See after an Airbag Inflates? . . . . . . . . . . . . . . 75
Passenger Sensing System . . . 77
Servicing the Airbag-Equipped Vehicle . . . . . . . . . . . . . . . . . . . . . . . 81
Adding Equipment to the Airbag-Equipped Vehicle . . . . . 81
Airbag System Check . . . . . . . . . . 82
Replacing Airbag System Parts after a Crash . . . . . . . . . . . . . . . . . 83
Child Restraints
Older Children . . . . . . . . . . . . . . . . . 83
Infants and Young Children . . . . 85
Child Restraint Systems . . . . . . . 87
Where to Put the Restraint . . . . . 89
Lower Anchors and Tethers forChildren (LATCH System) . . . . 90 Replacing LATCH System Parts
After a Crash . . . . . . . . . . . . . . . . . 96
Securing Child Restraints (With the Seat Belt in the
Rear Seat) . . . . . . . . . . . . . . . . . . . 97
Securing Child Restraints (With the Seat Belt in the
Front Seat) . . . . . . . . . . . . . . . . . . . 99