
Black plate (19,1)Buick LaCrosse Owner Manual - 2012
Driving and Operating 9-19
{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,
turn the ignition to ACC/
ACCESSORY.
The ignition switch can bind in the
LOCK/OFF position with the wheels
turned off center. If this happens,
move the steering wheel from right
to left while turning the key to ACC/
ACCESSORY. If this does not work,
then the vehicle needs service. B (ACC/ACCESSORY):
This
position provides power to some of
the electrical accessories. It unlocks
the ignition. To move the key from
ACC/ACCESSORY to LOCK/OFF,
the shift lever must be in P (Park).
C (ON/RUN): The ignition switch
stays in this position when the
engine is running. This position can
be used to operate the electrical
accessories, including the
ventilation fan and 12‐volt power
outlet, as well as to display some
warning and indicator lights. This
position can also be used for
service and diagnostics, and to
verify the proper operation of the
malfunction indicator lamp as may
be required for emission inspection
purposes. The transmission is also
unlocked in this position. The battery could be drained if the
key is left in the ACC/ACCESSORY
or ON/RUN position with the engine
off. The vehicle might not restart if
the battery is allowed to drain for an
extended period of time.
D (START):
This position starts the
engine. When the engine starts,
release the key. The ignition switch
will return to ON/RUN for normal
driving.
A warning tone sounds when the
driver door is opened when the
ignition is still in ACC/ACCESSORY
and the key is in the ignition.

Black plate (31,1)Buick LaCrosse Owner Manual - 2012
Driving and Operating 9-31
{WARNING
It can be dangerous to get out of
the vehicle if the automatic
transmission shift lever is not fully
in P (Park) with the parking brake
firmly set. The vehicle can roll. Do
not leave the vehicle when the
engine is running unless you
have to. 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,
always set the parking brake and
move the shift lever to P (Park).
Follow the proper steps to be sure
the vehicle will not move. See
Shifting Into Park on page 9‑27.
If parking on a hill and pulling a
trailer, see Driving Characteristics
and Towing Tips on page 9‑57.
Automatic
Transmission
The automatic transmission has a
shift lever located on the console
between the seats.
P (Park): This position locks the
front wheels. It is the best position
to use when starting the engine
because the vehicle cannot move
easily.
{WARNING
It is 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.
Do not leave the vehicle when the
engine is running unless you
have to. 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,
always set the parking brake and
move the shift lever to P (Park).
See Shifting Into Park on
page 9‑27. If you are pulling a
trailer, see Driving Characteristics
and Towing Tips on page 9‑57.
Make sure the shift lever is fully in
P (Park) before starting the engine.
The vehicle has an automatic
transmission shift lock control
system.

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 (35,1)Buick LaCrosse Owner Manual - 2012
Driving and Operating 9-35
Brakes
Antilock Brake
System (ABS)
This vehicle has the Antilock Brake
System (ABS), an advanced
electronic braking system that helps
prevent a braking skid.
When the engine is started and the
vehicle begins to drive away, ABS
checks itself. A momentary motor or
clicking noise might be heard while
this test is going on, and it might
even be noticed that the brake
pedal moves a little. This is normal.
If there is a problem with ABS, this
warning light stays on. SeeAntilock
Brake System (ABS) Warning Light
on page 5‑21. If driving safely on a wet road and it
becomes necessary to slam on the
brakes and continue braking to
avoid a sudden obstacle, a
computer senses that the wheels
are slowing down. If one of the
wheels is about to stop rolling, the
computer will separately work the
brakes at each wheel.
ABS can change the brake pressure
to each wheel, as required, faster
than any driver could. This can help
the driver steer around the obstacle
while braking hard.
As the brakes are applied, the
computer keeps receiving updates
on wheel speed and controls
braking pressure accordingly.
Remember: ABS does not change
the time needed to get a foot up to
the brake pedal or always decrease
stopping distance. If you get too
close to the vehicle in front of you,
there will not be enough time to
apply the brakes if that vehicle
suddenly slows or stops. Always
leave enough room up ahead to
stop, even with ABS.
Using ABS
Do not pump the brakes. Just hold
the brake pedal down firmly and let
ABS work. You might hear the ABS
pump or motor operating and feel
the brake pedal pulsate, but this is
normal.
Braking in Emergencies
ABS allows the driver to steer and
brake at the same time. In many
emergencies, steering can help
more than even the very best
braking.

Black plate (37,1)Buick LaCrosse Owner Manual - 2012
Driving and Operating 9-37
If the parking brake warning light is
on, the EPB has detected an error
in another system and is operating
with reduced functionality. To apply
the EPB when this light is on, lift up
on the EPB switch and hold it in the
up position. Full application of the
parking brake by the EPB system
may take longer than normal when
this light is on. Continue to hold the
switch until the parking brake status
light remains on. If the parking
brake warning light is on, see your
dealer.
If the EPB fails to apply, the rear
wheels should be blocked to
prevent vehicle movement.
EPB Release
To release the EPB, place the
ignition in the ON/RUN position,
apply and hold the brake pedal, and
push down momentarily on the EPB
switch. If you attempt to release the
EPB without the brake pedal
applied, a chime will sound, and aDIC message will be displayed. See
Brake System Messages on
page 5‑36. The EPB is released
when the parking brake status light
is off.
If the parking brake warning light is
on, the EPB has detected an error
in another system and is operating
with reduced functionality. To
release the EPB when this light is
on, push down on the EPB switch
and hold it in the down position.
EPB release may take longer than
normal when this light is on.
Continue to hold the switch until the
parking brake status light is off.
If the light is on, see your dealer.
Notice:
Driving with the parking
brake on can overheat the brake
system and cause premature
wear or damage to brake system
parts. Make sure that the parking
brake is fully released and the
brake warning light is off before
driving.
Automatic EPB Release
The EPB will automatically release if
the vehicle is running, placed into
gear, and an attempt is made to
drive away. Avoid rapid acceleration
when the EPB is applied, to
preserve parking brake lining life.
For maximum EPB force when
towing a trailer or parking on a hill,
pull the EPB switch twice. If you are
towing a trailer and parking on a hill,
see Driving Characteristics and
Towing Tips on page 9‑57 for more
information.

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 (39,1)Buick LaCrosse Owner Manual - 2012
Driving and Operating 9-39
dflashes to indicate that TCS is
active. See Traction Control System
(TCS)/StabiliTrak
®Light on
page 5‑23 for more information.
If there is a problem detected with
TCS, SERVICE TRACTION
CONTROL is displayed on the
Driver Information Center (DIC).
See Ride Control System Messages
on page 5‑40. When this message
is displayed and
dcomes on and
stays on, the vehicle is safe to drive
but the system is not operational.
Driving should be adjusted
accordingly.
If
dcomes on and stays on, reset
the system.
To reset:
1. Stop the vehicle.
2. Turn the engine off and wait 15 seconds.
3. Start the engine. If
dstill comes on and stays on, the
vehicle needs service.
Notice: Do not repeatedly brake
or accelerate heavily when TCS is
off. The vehicle's driveline could
be damaged.
TCS can be turned off by pressing
and releasing the TCS/StabiliTrak
button. When TCS is turned off,
i
comes on, and the appropriate DIC message also displays. See
Ride
Control System Messages on
page 5‑40. With TCS turned off, the
system does not limit wheel slip.
Driving should be adjusted
accordingly. See Traction Off Light
on page 5‑22 for more information.
Press and release the TCS/
StabiliTrak button again to turn the
system back on.
It may be necessary to turn the
system off if the vehicle gets stuck
in sand, mud, or snow and rocking
the vehicle is required. See If the
Vehicle Is Stuck on page 9‑11 for
more information. See also Winter
Driving on page 9‑9 for information
on using TCS when driving in snowy
or icy conditions.
Adding non‐GM accessories can
affect the vehicle performance. See
Accessories and Modifications on
page 10‑3 for more information.