2007 BUICK LACROSSE ECU

The passenger sensing system works with sensors
that are part of the right front passenger’s seat. The
sensors are designed to detect the presence of a
properly-seated occupant and determine if the
passenger’s frontal airbag should be enabled
(may inate) or not.
Accident statistics show that children are safer if
they are restrained in the rear rather than the front
seat. We recommend that child restraints be
secured in a rear seat, including an infant riding
in a rear-facing infant seat, a child riding in a
forward-facing child seat, and an older child riding
in a booster seat.
Your vehicle has a rear seat that will accommodate
a rear-facing child restraint. A label on your sun
visor says, “Never put a rear-facing child seat
in the front.” This is because the risk to the
rear-facing child is so great, if the airbag deploys.
{CAUTION:
A child in a rear-facing child restraint can
be seriously injured or killed if the right
front passenger’s airbag inates. This is
because the back of the rear-facing child
restraint would be very close to the
inating airbag.
Even though the passenger sensing
system is designed to turn off the
passenger’s frontal airbag if the system
detects a rear-facing child restraint,
no system is fail-safe, and no one can
guarantee that an airbag will not deploy
under some unusual circumstance, even
though it is turned off. We recommend
that rear-facing child restraints be secured
in the rear seat, even if the airbag is off.
CAUTION: (Continued)
76

CAUTION: (Continued)
If you need to secure a forward-facing
child restraint in the right front seat,
always move the front passenger seat as
far back as it will go. It is better to secure
the child restraint in a rear seat.
The passenger sensing system is designed to turn
off the right front passenger’s frontal airbag if:
The right front passenger seat is unoccupied.
The system determines that an infant is
present in a rear-facing infant seat.
The system determines that a small child is
present in a forward-facing child restraint.
The system determines that a small child is
present in a booster seat.
A right front passenger takes his/her weight off
of the seat for a period of time.
The right front passenger seat is occupied by
a smaller person, such as a child who has
outgrown child restraints.
Or, if there is a critical problem with the airbag
system or the passenger sensing system.
When the passenger sensing system has turned
off the right front passenger’s frontal airbag, the off
indicator on the instrument panel will light and
stay lit to remind you that the airbag is off.
If a child restraint has been installed and the on
indicator is lit, turn the vehicle off. Remove the child
restraint from the vehicle and reinstall the child
restraint following the child restraint manufacturer’s
directions and refer toSecuring a Child Restraint in
the Right Front Seat Position on page 61.
If, after reinstalling the child restraint and restarting
the vehicle, the on indicator is still lit, check to make
sure that the vehicle’s seatback is not pressing the
child restraint into the seat cushion. If this happens,
slightly recline the vehicle’s seatback and adjust the
seat cushion if possible. Also make sure the child
restraint is not trapped under the vehicle head
restraint. If this happens, adjust the head restraint.
77

If the on indicator is still lit, secure the child in the
child restraint in a rear seat position in the vehicle
and check with your dealer.
The passenger sensing system is designed to
enable (may inate) the right front passenger’s
frontal airbag anytime the system senses that a
person of adult size is sitting properly in the right
front passenger’s seat. When the passenger
sensing system has allowed the airbag to be
enabled, the on indicator will light and stay lit to
remind you that the airbag is active.
For some children who have outgrown child
restraints and for very small adults, the passenger
sensing system may or may not turn off the right
front passenger’s frontal airbag, depending upon
the person’s seating posture and body build.
Everyone in your vehicle who has outgrown
child restraints should wear a safety belt
properly — whether or not there is an airbag
for that person.
If a person of adult-size is sitting in the
right front passenger’s seat, but the off
indicator is lit, it could be because that
person is not sitting properly in the seat.If this happens, turn the vehicle off and ask the
person to place the seatback in the fully upright
position, then sit upright in the seat, centered on the
seat cushion, with the person’s legs comfortably
extended. Restart the vehicle and have the person
remain in this position for about two minutes. This
will allow the system to detect that person and then
enable the passenger’s airbag.
78

{CAUTION:
If the airbag readiness light in the
instrument panel cluster ever comes on
and stays on, it means that something may
be wrong with the airbag system. If this
ever happens, have the vehicle serviced
promptly, because an adult-size person
sitting in the right front passenger’s seat
may not have the protection of the frontal
airbag. SeeAirbag Readiness Light on
page 182for more on this, including
important safety information.
A thick layer of additional material such as a
blanket, or aftermarket equipment such as seat
covers, seat heaters, and seat massagers, can
affect how well the passenger sensing system
operates. Remove any additional material from
the seat cushion before reinstalling or securing
the child restraint and before a small occupant,
including a small adult, sits in the right front
passenger’s seat. You may want to consider notusing seat covers or other aftermarket equipment if
your vehicle has the passenger sensing system.
SeeAdding Equipment to Your Airbag-Equipped
Vehicle on page 81for more information about
modications that can affect how the system
operates.
The passenger sensing system may suppress the
airbag deployment when liquid is soaked into the
seat. If this happens, the off indicator in the
passenger airbag status indicator and the airbag
readiness light on the instrument panel will be lit.
The system should resume normal operation after
the seat is allowed to dry. If the system operates
incorrectly after the seat has dried, have your
dealer check the system.
{CAUTION:
Stowing of articles under the passenger’s
seat or between the passenger’s seat
cushion and seatback may interfere with
the proper operation of the passenger
sensing system.
79

Adding Equipment to Your
Airbag-Equipped Vehicle
Q:Is there anything I might add to the front
or sides of the vehicle that could keep the
airbags from working properly?
A:Yes. If you add things that change your
vehicle’s frame, bumper system, height, front
end or side sheet metal, they may keep the
airbag system from working properly. Also, the
airbag system may not work properly if you
relocate any of the airbag sensors. If you have
any questions about this, you should contact
Customer Assistance before you modify your
vehicle. The phone numbers and addresses for
Customer Assistance are in Step Two of the
Customer Satisfaction Procedure in this
manual. SeeCustomer Satisfaction
Procedure on page 478.
Q:Because I have a disability, I have to get
my vehicle modied. How can I nd out
whether this will affect my airbag system?
A:Changing or moving any parts of the front
seats, safety belts, the airbag sensing and
diagnostic module, steering wheel, instrument
panel, ceiling headliner, ceiling and pillar
garnish trim, roof-mounted airbag modules,
or airbag wiring can affect the operation of the
airbag system. If you have questions, call
Customer Assistance. The phone numbers
and addresses for Customer Assistance are in
Step Two of the Customer Satisfaction
Procedure in this manual. SeeCustomer
Satisfaction Procedure on page 478.
81

Keys.............................................................. 87
Remote Keyless Entry (RKE) System.......... 89
Remote Keyless Entry (RKE) System
Operation................................................. 90
Doors and Locks.......................................... 96
Door Locks................................................. 96
Power Door Locks....................................... 97
Delayed Locking.......................................... 97
Automatic Door Lock................................... 98
Programmable Automatic Door Unlock........ 98
Rear Door Security Locks........................... 98
Lockout Protection....................................... 99
Trunk........................................................ 100
Windows...................................................... 102
Power Windows........................................ 103
Sun Visors................................................ 104
Theft-Deterrent Systems............................. 104
Content Theft-Deterrent............................. 104
PASS-Key
®III ........................................... 106
PASS-Key®III Operation........................... 107Starting and Operating Your Vehicle......... 109
New Vehicle Break-In................................ 109
Ignition Positions....................................... 109
Retained Accessory Power (RAP)............. 110
Starting the Engine.................................... 111
Engine Coolant Heater.............................. 112
Automatic Transaxle Operation.................. 114
Parking Brake........................................... 117
Shifting Into Park (P) ................................. 118
Shifting Out of Park (P)............................. 120
Parking Over Things That Burn................. 121
Engine Exhaust......................................... 122
Running the Engine While Parked............. 123
Mirrors......................................................... 124
Manual Rearview Mirror............................. 124
Manual Rearview Mirror with OnStar
®....... 124
Automatic Dimming Rearview Mirror.......... 124
Automatic Dimming Rearview Mirror
with OnStar
®.......................................... 125
Outside Power Mirrors............................... 125
Outside Power Heated Mirrors................... 126
Outside Convex Mirror............................... 126
Section 2 Features and Controls
85

Automatic Door Lock
The vehicle’s doors are programmed to lock when
the shift lever is moved into a forward gear.
If someone needs to get in or out of the vehicle after
the doors have been locked, place the shift lever
into PARK (P). You may also unlock all doors using
the power door lock switch or unlock one door using
the inside manual door lock.
The automatic door lock feature cannot be
disabled.
Programmable Automatic Door
Unlock
The vehicle’s doors are programmed from the
factory to unlock when the shift lever is moved
into PARK (P).
If your vehicle has a Driver Information
Center (DIC), there are different programming
options for unlocking the doors automatically.
SeeDIC Vehicle Personalization on page 229.
Rear Door Security Locks
Your vehicle has rear door security locks. These
prevent passengers from opening the rear
doors from the inside.
The rear door security
locks are located on the
inside edge of each
rear door. You must
open the rear doors to
access them.
To set the locks, do the following:
1. Insert the key into the security lock slot and
turn it so the slot is in the horizontal position.
2. Close the door.
98

When you want to open a rear door when the
security lock is on, do the following:
1. Unlock the door using the remote keyless
entry transmitter, if equipped, the power
door lock switch, or by lifting the rear door
manual lock.
2. Open the door from the outside.
To cancel the rear door security lock, do the
following:
1. Unlock the door and open it from the outside.
2. Insert the key into the security lock slot
and turn it so the slot is in the vertical position.Lockout Protection
The lockout protection feature makes it more
difficult to lock the key in the vehicle. If the driver’s
door is open while the key is in the ignition, the
door cannot be locked with the power door
lock switch.
This feature cannot guarantee that you will never be
locked out of the vehicle. If the key is not left in the
ignition, or, if the manual door lock is used, the key
could still be locked inside the vehicle. Always
remember to take the key with you.
99