
Black plate (20,1)Buick LaCrosse Owner Manual - 2012
9-20 Driving and Operating
Ignition Positions
(Keyless Access)
The vehicle has an electronic
keyless ignition with pushbutton
start.
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. See
Remote Keyless Entry
(RKE) System Operation on
page 2‑4 for more information.
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 LED
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 9‑27 for more
information. 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 5‑42 for more information.
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.

Black plate (21,1)Buick LaCrosse Owner Manual - 2012
Driving and Operating 9-21
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
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 9‑36.
{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,
switch the ignition to ACC/
ACCESSORY.
ACC/ACCESSORY (Amber LED
Light):
This mode allows you to
use some electrical accessories
when the engine is off.
With the ignition off, pressing the
button one time without the brake
pedal applied will place the ignition
system in ACC/ACCESSORY.
The ignition will switch from ACC/
ACCESSORY to OFF after
five minutes to prevent battery
rundown.
ON/RUN/START (Green LED
Light): This mode is for driving and
starting. With the ignition off, and
the brake pedal applied, pressing
the button once will place the
ignition system in ON/RUN/START.
Once engine cranking begins,
release the button. Engine cranking
will continue until the engine starts. See
Starting the Engine on
page 9‑22 for more information. The
ignition will then remain in ON/RUN.
Service Only Mode
This power mode is available for
service and diagnostics, and to
verify the proper operation of the
malfunction indicator lamp as may
be required for emission inspection
purposes. With the vehicle off, and
the brake pedal not applied,
pressing and holding the button for
more than five seconds will place
the vehicle in Service Only Mode.
The instruments and audio systems
will operate as they do in ON/RUN,
but the vehicle will not be able to be
driven. The engine will not start in
Service Only Mode. Push the button
again to turn the vehicle off.

Black plate (27,1)Buick LaCrosse Owner Manual - 2012
Driving and Operating 9-27
{WARNING
Plugging the cord into an
ungrounded outlet could cause an
electrical shock. Also, the wrong
kind of extension cord could
overheat and cause a fire. You
could be seriously injured. Plug
the cord into a properly grounded
three-prong 110-volt AC outlet.
If the cord will not reach, use a
heavy-duty three-prong extension
cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and store the
cord as it was before to keep it
away from moving engine parts.
The length of time the heater should
remain plugged in depends on
several factors. Ask a dealer in the
area where you will be parking the
vehicle for the best advice on this.
Retained Accessory
Power (RAP)
These vehicle accessories can be
used for up to 10 minutes after the
engine is turned off:
.Audio System
.Power Windows
.Sunroof (If Equipped)
.Auxiliary Power Outlet
Power to the audio system will
continue to operate for up to
10 minutes or until the driver door is
opened.
Power to the power windows and
sunroof will continue to operate for
up to 10 minutes or until any door is
opened.
All of these features will work when
the ignition is in ON/RUN or ACC/
ACCESSORY.
Shifting Into Park
{WARNING
It can be 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. 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, use the steps
that follow.
1. Hold the brake pedal down and set the parking brake.
See Parking Brake on page 9‑36
for more information.
2. Move the shift lever into P (Park) by pushing the lever all the way
toward the front of the vehicle.
3. Turn the ignition off.

Black plate (32,1)Buick LaCrosse Owner Manual - 2012
9-32 Driving and Operating
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. SeeShifting out of Park on
page 9‑29.
R (Reverse): Use this gear to
back up.
Notice: 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. To rock the vehicle back and forth to
get out of snow, ice, or sand without
damaging the transmission, see
If
the Vehicle Is Stuck on page 9‑11.
N (Neutral): In this position, the
engine does not connect with the
wheels. To restart the engine when
the vehicle is already moving, use
N (Neutral) only. Also, use
N (Neutral) when the vehicle is
being towed.
{WARNING
Shifting into a drive gear while the
engine is running at high speed is
dangerous. Unless your foot is
firmly on the brake pedal, the
vehicle could move very rapidly.
You could lose control and hit
people or objects. Do not shift
into a drive gear while the engine
is running at high speed. Notice:
Shifting out of P (Park) or
N (Neutral) with the engine
running at high speed may
damage the transmission. The
repairs would not be covered by
the vehicle warranty. Be sure the
engine is not running at high
speed when shifting the vehicle.
D (Drive): This position is for
normal driving. It provides the best
fuel economy. If more power is
needed for passing, and the
vehicle is:.Going less than 56 km/h
(35 mph), push the accelerator
pedal about halfway down.
.Going about 56 km/h (35 mph) or
more, push the accelerator all
the way down.

Black plate (34,1)Buick LaCrosse Owner Manual - 2012
9-34 Driving and Operating
Uplevel Display Shown, BaseModel Similar
The display on the instrument panel
cluster will show which gear the
vehicle is in. The number indicates
the requested gear range when
moving the shift lever forward or
rearward. The transmission will only allow
you to shift into gears appropriate
for the vehicle speed and engine
revolutions per minute (rpm). The
transmission will not automatically
shift to the next lower gear if the
engine rpm is too high, nor to the
next higher gear when the maximum
engine rpm is reached.
While in the DSC mode, the
transmission will automatically
downshift when the vehicle comes
to a stop. This will allow for more
power during take-off.
When accelerating the vehicle from
a stop in snowy and icy conditions,
you may want to shift into second
gear. A higher gear allows you to
gain more traction on slippery
surfaces.
Drive Systems
All-Wheel Drive
Vehicles with this feature always
send engine power to all four
wheels. It is fully automatic, and
adjusts itself as needed for road
conditions.
When using a compact spare tire on
an AWD vehicle, the system
automatically detects the compact
spare and disables AWD. To restore
AWD operation and prevent
excessive wear on the system,
replace the compact spare with a
full-size tire as soon as possible.
See
Compact Spare Tire on
page 10‑93 for more information.

Black plate (36,1)Buick LaCrosse Owner Manual - 2012
9-36 Driving and Operating
Parking Brake
The vehicle has an Electric Parking
Brake (EPB). The switch for the
EPB is in the center console. The
EPB can always be activated, even
if the ignition is off. To prevent
draining the battery, avoid repeated
cycles of the EPB system when the
engine is not running.
The system has a parking brake
status light and a parking brake
warning light. SeeElectric Parking
Brake Light on page 5‑21. There are
also three Driver Information Center (DIC) messages. See
Brake System
Messages on page 5‑36 for more
information. In case of insufficient
electrical power, the EPB cannot be
applied or released.
Before leaving the vehicle, check
the parking brake status light to
ensure that the parking brake is
applied.
EPB Apply
The EPB can be applied any time
the vehicle is stopped. The EPB is
applied by momentarily lifting up on
the EPB switch. Once fully applied,
the parking brake status light will be
on. While the brake is being applied,
the status light will flash until full
apply is reached. If the light does
not come on, or remains flashing,
have the vehicle serviced. Do not
drive the vehicle if the parking brake
status light is flashing. See your
dealer. See Electric Parking Brake
Light on page 5‑21 for more
information. If the EPB is applied while the
vehicle is in motion, a chime will
sound, and a DIC message will be
displayed. See
Brake System
Messages on page 5‑36. The
vehicle will decelerate as long as
the switch is held in the up position.
Releasing the EPB switch during
deceleration will release the parking
brake. If the switch is held in the up
position until the vehicle comes to a
stop, the EPB will remain applied.
If the parking brake status light
flashes continuously, the EPB is
only partially applied or released,
or there is a problem with the EPB.
A DIC message will be displayed.
See Brake System Messages on
page 5‑36. If this light flashes
continuously, release the EPB, and
attempt to apply it again. If this light
continues to flash, do not drive the
vehicle. See your dealer.

Black plate (38,1)Buick LaCrosse Owner Manual - 2012
9-38 Driving and Operating
Brake Assist
This vehicle has a brake assist
feature designed to assist the driver
in stopping or decreasing vehicle
speed in emergency driving
conditions. This feature uses the
stability system hydraulic brake
control module to supplement the
power brake system under
conditions where the driver has
quickly and forcefully applied the
brake pedal in an attempt to quickly
stop or slow down the vehicle. The
stability system hydraulic brake
control module increases brake
pressure at each corner of the
vehicle until the ABS activates.
Minor brake pedal pulsation or
pedal movement during this time is
normal and the driver should
continue to apply the brake pedal as
the driving situation dictates. The
brake assist feature will
automatically disengage when the
brake pedal is released or brake
pedal pressure is quickly
decreased.
Hill Start Assist (HSA)
This vehicle has a Hill Start Assist
(HSA) feature, which may be useful
when the vehicle is stopped on a
grade. This feature is designed to
prevent the vehicle from rolling,
either forward or rearward, during
vehicle drive off. After the driver
completely stops and holds the
vehicle in a complete standstill on a
grade, HSA will be automatically
activated. During the transition
period between when the driver
releases the brake pedal and starts
to accelerate to drive off on a grade,
HSA holds the braking pressure to
ensure that there is no rolling. The
brakes will automatically release
when the accelerator pedal is
applied within the two‐second
window. It will not activate if the
vehicle is in a drive gear and facing
downhill or if the vehicle is facing
uphill and in R (Reverse).
Ride Control Systems
Traction Control
System (TCS)
The vehicle has a Traction Control
System (TCS) that limits wheel slip.
The system operates if it senses
that one or both of the front wheels
are slipping or beginning to lose
traction. When this happens, the
system reduces engine power and/
or applies brake pressure to the
slipping wheel(s).
The system may be heard or felt
while it is working, but this is
normal.
TCS automatically comes on
whenever the vehicle is started. To
limit wheel slip, especially in
slippery road conditions, the system
should always be left on. But, TCS
can be turned off if needed.

Black plate (1,1)Buick LaCrosse Owner Manual - 2012
Vehicle Care 10-1
Vehicle Care
General Information
General Information . . . . . . . . . . 10-2
California Proposition65 Warning . . . . . . . . . . . . . . . . . 10-3
California Perchlorate Materials Requirements . . . . 10-3
Accessories and Modifications . . . . . . . . . . . . . . . 10-3
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 10-4
Hood . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . 10-6
Engine Oil . . . . . . . . . . . . . . . . . . . 10-9
Engine Oil Life System . . . . . 10-12
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . 10-13
Engine Air Cleaner/Filter . . . . 10-13
Cooling System . . . . . . . . . . . . 10-15
Engine Coolant . . . . . . . . . . . . . 10-16
Engine Overheating . . . . . . . . 10-19
Overheated Engine Protection
Operating Mode . . . . . . . . . . . 10-21 Power Steering Fluid (2.4L
L4 Engine) . . . . . . . . . . . . . . . . 10-21
Power Steering Fluid (3.6L V6 Engine) . . . . . . . . . . . . . . . . 10-21
Washer Fluid . . . . . . . . . . . . . . . 10-22
Brakes . . . . . . . . . . . . . . . . . . . . . 10-23
Brake Fluid . . . . . . . . . . . . . . . . . 10-24
Battery . . . . . . . . . . . . . . . . . . . . . 10-25
Starter Switch Check . . . . . . . 10-27
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . 10-27
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . 10-28
Park Brake and P (Park) Mechanism Check . . . . . . . . 10-28
Wiper Blade Replacement . . . . . . . . . . . . . . 10-29
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . 10-30
Bulb Replacement
Bulb Replacement . . . . . . . . . . 10-33
Halogen Bulbs . . . . . . . . . . . . . . 10-33
High Intensity Discharge(HID) Lighting . . . . . . . . . . . . . 10-33 Headlamps, Front Turn
Signal and Parking
Lamps . . . . . . . . . . . . . . . . . . . . 10-33
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . 10-35
License Plate Lamp . . . . . . . . 10-36
Replacement Bulbs . . . . . . . . . 10-36
Electrical System
High Voltage Devices and Wiring . . . . . . . . . . . . . . . . . . . . . 10-37
Electrical System Overload . . . . . . . . . . . . . . . . . . 10-37
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . 10-38
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . 10-38
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . 10-42
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . 10-44
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . 10-47
Winter Tires . . . . . . . . . . . . . . . . 10-48
Tire Sidewall Labeling . . . . . . 10-48
Tire Designations . . . . . . . . . . . 10-51