
Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
Driving and Operating 171
Warning (Continued)
systems and disable the airbags.
While driving, only shut the
vehicle off in an emergency.
If the ignition 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.
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 press ENGINE
START/STOP.
4. Set the parking brake. See Electric Parking Brake 0188. If the vehicle cannot be pulled over
and must be shut off while driving,
press and hold ENGINE START/
STOP for longer than two seconds,
or press twice in five seconds.
ACC/ACCESSORY (Amber
Indicator Light) :
This mode allows
you to use some electrical
accessories when the ignition is off.
With the ignition off, pressing
ENGINE START/STOP once without
the brake pedal applied will place
the ignition system in ACC/
ACCESSORY.
The ignition will switch from ACC/
ACCESSORY to OFF after
10 minutes to prevent battery
rundown.
ON/RUN/START (Green Indicator
Light) : This mode is for driving and
starting. With the ignition off and the
brake pedal applied, pressing
ENGINE START/STOP 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 0172. The ignition will then
remain in ON/RUN.
Service Mode
This power mode is available for
service and diagnostics. See
Automatic Transmission 0181.
Service Mode is also available to
verify the proper operation of the
malfunction indicator lamp as may
be required for emission inspection
purposes. With the ignition off and
the brake pedal not applied,
pressing and holding ENGINE
START/STOP for more than
five seconds will place the vehicle in
Service 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 Mode. Press
ENGINE START/STOP again to turn
the vehicle off.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
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Driving and Operating 173
starting it. Operate the engine
and transmission gently until
the oil warms up and lubricates
all moving parts.
Stop/Start System
{Warning
Exiting the vehicle without first
shifting into P (Park) may cause
the vehicle to move. You or others
may be injured. Because the
vehicle may have an auto engine
stop/start feature, the vehicle's
engine might seem to be shut off;
however, once the brake pedal is
released, the engine will start up
again.
Shift to P (Park) and turn the
ignition off before exiting the
vehicle.
The vehicle may be equipped with a
fuel saving Stop/Start system to
shut off the engine to help
conserve fuel.
Auto Stop (Vehicles without
eAssist)
If equipped, when the brakes are
applied and the vehicle is at a
complete stop, the engine may turn
off. When stopped, the tachometer
displays AUTO STOP. See
Tachometer 0112. When the brake
pedal is released or the accelerator
pedal is pushed, the engine will
restart.
The vehicle may remain in Auto
Stop even after it is shifted into
P (Park). Auto Stop will be
maintained until the door is opened
or the seat belt is unbuckled. There are several conditions that
may prevent an Auto Stop or cause
an Auto Start.
Auto Stop may be deactivated if:
.
A minimum vehicle speed is not
reached.
. The engine or transmission is
not at the required operating
temperature.
. The outside temperature is not
in the required operating range,
typically below −10 °C (14 °F) or
above 50 °C (122 °F).
. The transmission is in any gear
other than D (Drive).
. The battery charge is low.
. The battery has been
disconnected.
. The system may not be able to
shut off the engine in order to
maintain the air conditioning
comfort level or defrost system
settings. See Dual Automatic
Climate Control System 0152.
To maximize fuel economy, use
the ECO air conditioning mode.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
174 Driving and Operating
.The Auto Stop time is greater
than two minutes.
Auto Stop (Vehicles with
eAssist)
If equipped, when the brakes are
applied and the vehicle is at a
complete stop, the engine may turn
off. When stopped, the tachometer
displays AUTO STOP. See
Tachometer 0112. When the brake
pedal is released or the accelerator
pedal is pushed, the engine will
restart.
The vehicle may remain in Auto
Stop for up to two minutes. The vehicle may remain in Auto
Stop even after it is shifted into
P (Park). If the driver opens the door
or unbuckles the seat belt the
vehicle will exit Auto Stop and
restart the engine.
There are several conditions that
may prevent an Auto Stop or cause
an Auto Start.
Auto Stop may be
deactivated when:
.
The engine, transmission,
or high voltage battery is not at
the required operating
temperature.
. The outside temperature is not
in the required operating range,
typically below −20 °C (−4 °F).
. The system may not be able to
shut off the engine in order to
maintain the air conditioning
comfort level or defrost system
settings. See Dual Automatic
Climate Control System 0152.
To maximize fuel economy, use
the ECO air conditioning mode. .
The transmission is in any gear
other than D (Drive).
. The high voltage battery charge
is low.
. The hood is not fully closed.
. The malfunction indicator lamp
is on.
. High humidity is detected.
The Engine Will Restart when:
. The brake pedal is released.
. The accelerator pedal is applied.
. Shifting out of D (Drive) to any
other gear besides P (Park).
. The air conditioning or defrost
system needs the compressor to
maintain interior comfort. See
Dual Automatic Climate Control
System 0152. To maximize fuel
economy, use the ECO air
conditioning mode.
. The engine is required to run for
either heater or climate control
performance, or the climate
control system is turned from off

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
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Driving and Operating 185
To shift out of D (Drive):1. Bring the vehicle to a complete stop.
2. Shift to the desired gear.
3. After releasing the shift lever, it will return to the center
position.
Downshifting the transmission in
slippery road conditions could result
in skidding. See “Skidding”under
Loss of Control 0163.
Caution
Spinning the tires or holding the
vehicle in one place on a hill
using only the accelerator pedal
may damage the transmission.
The repair will not be covered by
the vehicle warranty. If the vehicle
is stuck, do not spin the tires.
When stopping on a hill, use the
brakes to hold the vehicle in
place.
Caution
A transmission hot message may
display if the automatic
transmission fluid is too hot.
Driving under this condition can
damage the vehicle. Stop and idle
the engine to cool the automatic
transmission fluid. This message
clears when the transmission fluid
has cooled sufficiently.
SERVICE SHIFTER SEE
OWNER’S MANUAL Message
When this message displays in the
Driver Information Center (DIC), the
shift lever needs service. Have the
vehicle serviced as soon as
possible. If the vehicle is
automatically shifting into P (Park),
check to see if the P (Park) button
on top of the shifter is stuck. To
operate the vehicle, hold the shift
lever in the desired gear,
R (Reverse) or D (Drive), until
vehicle speed exceeds 15 km/h
(10 mph), then release the shift
lever.
Manual Mode
Tap Shift Caution
Driving with the engine at a high
rpm without upshifting while using
Tap Shift, could damage the
vehicle. Always upshift when
necessary while using Tap Shift.
Vehicles with Tap Shift have
controls on the back of the steering
wheel to manually shift the
automatic transmission.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
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Driving and Operating 187
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.
All-Wheel Drive (AWD) system
performance will be automatically
reduced when the compact spare
tire is in use. To restore full AWD
performance, and prevent excessive
wear to the AWD system, replace
the compact spare tire with a
full-size tire as soon as possible.
SeeCompact Spare Tire 0292.
Brakes
Antilock Brake
System (ABS)
This vehicle has an Antilock Brake
System (ABS), an advanced
electronic braking system that helps
prevent a braking skid.
When the vehicle begins to drive
away, ABS checks itself.
A momentary motor or clicking noise
may be heard while this test is going
on, and it may 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. See Antilock
Brake System (ABS) Warning Light
0 120. 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 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
you 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.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
188 Driving and Operating
Using ABS
Do not pump the brakes. Just hold
the brake pedal down firmly and let
ABS work. You may hear the ABS
pump or motor operating and feel
the brake pedal pulsate. This is
normal.
Braking in Emergencies
ABS allows you to steer and brake
at the same time. In many
emergencies, steering can help
more than even the very best
braking.
Electric Parking Brake
The Electric Parking Brake (EPB)
can always be activated, even if the
ignition is off. To prevent draining
the battery, avoid repeated cycles of
the EPB when the engine is not
running.
The system has a red parking brake
status light and an amber parking
brake warning light. There are also
parking brake-related Driver
Information Center (DIC) messages.
In case of insufficient electrical
power, the EPB cannot be applied
or released.
Before leaving the vehicle, check
the red parking brake status light to
ensure that the parking brake is
applied.
EPB Apply
To apply the EPB:1. Be sure the vehicle is at a complete stop.
2. Press the EPB switch momentarily.
The red parking brake status light
will flash and then stay on once the
EPB is fully applied. If the red parking brake status light flashes
continuously, then the EPB is only
partially applied or there is a
problem with the EPB. A DIC
message will display. Release the
EPB and try to apply it again. If the
light does not come on, or keeps
flashing, have the vehicle serviced.
Do not drive the vehicle if the red
parking brake status light is flashing.
See your dealer.
If the amber parking brake warning
light is on, press the EPB switch.
Continue to hold the switch until the
red parking brake status light
remains on. If the amber parking
brake warning light is on, see your
dealer.
If the EPB is applied while the
vehicle is moving, the vehicle will
decelerate as long as the switch is
pressed. If the switch is pressed
until the vehicle comes to a stop,
the EPB will remain applied.
The vehicle may automatically apply
the EPB in some situations when
the vehicle is not moving. This is

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
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190 Driving and Operating
pressure to hold the vehicle
stationary. If AVH is holding the
vehicle, a Driver Information Center
(DIC) message displays. AVH will
not activate in a forward drive gear
when facing downhill, or in
R (Reverse) when facing uphill.
Select the duration of the AVH
feature through vehicle
personalization. See“Comfort and
Convenience” inVehicle
Personalization 0133. When Short
and Auto Park Brake Off is selected,
the vehicle is held stationary for up
to two seconds after the brake pedal
is released. When Long and Auto
Park Brake On is selected, the
vehicle is held stationary for up to
five minutes after the brake pedal is
released. In either case, override
the hold feature by pressing the
accelerator pedal and attempting to
drive away. If Short and Auto Park Brake Off is
selected, it will hold the vehicle for
two seconds unless the driver door
is opened or the driver seat belt is
unbuckled after releasing the brake
pedal. If Long and Auto Park Brake
On is selected, it will hold the
vehicle for five minutes unless the
driver door is opened and the driver
seat belt is unbuckled prior to
releasing the brake pedal. When
deactivated after five minutes, or if it
is deactivated when the driver seat
belt is unlatched or the driver door is
opened, the Electric Parking Brake
will engage to prevent vehicle
movement.Ride Control Systems
Traction Control/
Electronic Stability
Control
System Operation
The vehicle has a Traction Control
System (TCS) and StabiliTrak®, an
electronic stability control system.
These systems help limit wheel slip
and assist the driver in maintaining
control, especially on slippery road
conditions.
TCS activates if it senses that any
of the drive wheels are spinning or
beginning to lose traction. When this
happens, TCS applies the brakes to
the spinning wheels and reduces
engine power to limit wheel spin.
StabiliTrak activates when the
vehicle senses a difference between
the intended path and the direction
the vehicle is actually traveling.
StabiliTrak selectively applies
braking pressure to any one of the

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
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Driving and Operating 191
vehicle wheel brakes to assist the
driver in keeping the vehicle on the
intended path.
If cruise control is being used and
traction control or StabiliTrak begins
to limit wheel spin, cruise control will
disengage. Cruise control may be
turned back on when road
conditions allow.
Both systems come on
automatically when the vehicle is
started and begins to move. The
systems may be heard or felt while
they are operating or while
performing diagnostic checks. This
is normal and does not mean there
is a problem with the vehicle.
It is recommended to leave both
systems on for normal driving
conditions, but it may be necessary
to turn TCS off if the vehicle gets
stuck in sand, mud, ice, or snow.
SeeIf the Vehicle Is Stuck 0166
and “Turning the Systems Off and
On” later in this section.
The indicator light for both systems
is in the instrument cluster. This
light will:
.
Flash when TCS is limiting
wheel spin.
. Flash when StabiliTrak is
activated.
. Turn on and stay on when either
system is not working.
If either system fails to turn on or to
activate, a message displays in the
Driver Information Center (DIC), and
dcomes on and stays on to
indicate that the system is inactive
and is not assisting the driver in
maintaining control. The vehicle is
safe to drive, but driving should be
adjusted accordingly. If
dcomes on and stays on:
1. Stop the vehicle.
2. Turn the engine off and wait 15 seconds.
3. Start the engine.
Drive the vehicle. If
dcomes on
and stays on, the vehicle may need
more time to diagnose the problem.
If the condition persists, see your
dealer.