change time BUICK LACROSSE 2015 User Guide

Black plate (2,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
6-2 Lighting
;(Parking Lamps):Turns on the
parking lamps, together with the
sidemarker lamps, taillamps, license
plate lamps, and instrument panel
lights.
5(Headlamps): Turns on the
headlamps, together with the
parking lamps, sidemarker lamps,
taillamps, license plate lamps, and
instrument panel lights.
Exterior Lamps Off
Reminder
A warning chime sounds if the driver
door is opened while the ignition is
off and the exterior lamps are on.
Headlamp High/
Low-Beam Changer
2 3
(Headlamp High/Low-Beam
Changer): Push the turn signal
lever away from you and release, to
turn the high beams on. To return to
low beams, push the lever again or
pull it toward you and release.
This indicator light turns on in the
instrument cluster when the
high-beam headlamps are on.
Flash-to-Pass
To flash the high beams, pull the
turn signal lever toward you, and
release.
Daytime Running
Lamps (DRL)
DRL can make it easier for others to
see the front of your vehicle during
the day. Fully functional DRL are
required on all vehicles first sold in
Canada. If equipped with High Intensity
Discharge (HID) headlamps, the
dedicated DRL will come on when
all of the following conditions
are met:
.The ignition is on.
.The exterior lamps control is
in AUTO.
.The light sensor determines it is
daytime.
.The parking brake is released or
the vehicle is not in P (Park).
When the DRL are on, the taillamps,
sidemarker lamps, instrument panel
lights, and other lamps will not
be on.
The DRL turn off when the
headlamps are turned to
Oor the
ignition is off.
This vehicle may have a DRL
disabling function. When the DRL
are on and a turn signal is activated,
the DRL on that side will be off until
the turn signal goes off.

Black plate (3,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Lighting 6-3
Automatic Headlamp
System
When the exterior lamp control is
set to AUTO and it is dark enough
outside, the headlamps come on
automatically.
There is a light sensor on top of the
instrument panel. Do not cover the
sensor; otherwise the headlamps
will come on when they are not
needed.
The system may also turn on the
headlamps when driving through a
parking garage or tunnel.If the vehicle is started in a dark
garage, the automatic headlamp
system comes on immediately. If it
is light outside when the vehicle
leaves the garage, there is a slight
delay before the automatic
headlamp system changes to the
DRL. During that delay, the
instrument cluster may not be as
bright as usual. Make sure the
instrument panel brightness control
is in the full bright position. See
Instrument Panel Illumination
Control on page 6-5.
When it is bright enough outside,
the headlamps will turn off or may
change to Daytime Running
Lamps (DRL).
The automatic headlamp system
turns off when the exterior lamp
control is turned to
Oor the ignition
is off.
Lights On with Wipers
If the windshield wipers are
activated in daylight with the engine
on, and the exterior lamp control is in AUTO, the headlamps, parking
lamps, and other exterior lamps
come on. The transition time for the
lamps coming on varies based on
wiper speed. When the wipers are
not operating, these lamps turn off.
Move the exterior lamp control to
P
or;to disable this feature.
Adaptive Forward
Lighting (AFL)
The AFL pivots the headlamps
horizontally to provide greater road
illumination while turning. To enable
AFL, set the exterior lamp control to
the AUTO position. Moving the
switch out of the AUTO position
deactivates the system. AFL
operates when the vehicle speed is
greater than 3 km/h (2 mph). AFL
does not operate when the
transmission is in R (Reverse). AFL
is not immediately operable after
starting the vehicle; driving a short
distance is required to calibrate the
AFL. See
Exterior Lamp Controls on
page 6-1.

Black plate (4,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
6-4 Lighting
Hazard Warning Flashers
|(Hazard Warning Flashers):
Press this button on the center
stack above the audio system, to
make the front and rear turn signal
lamps flash on and off. Press again
to turn the flashers off.
The hazard warning flashers turn on
automatically if the airbags deploy.
Turn and Lane-Change
Signals
Move the lever all the way up or
down to signal a turn.
An arrow on the instrument cluster
flashes in the direction of the turn or
lane change.
Raise or lower the lever until the
arrow starts to flash to signal a lane
change. Hold it there until the lane
change is completed. If the lever is
briefly pressed and released, the
turn signal flashes three times. The turn and lane-change signal
can be turned off manually by
moving the lever back to its original
position.
If after signaling a turn or lane
change the arrow flashes rapidly or
does not come on, a signal bulb
might be burned out.
Have any burned out bulbs
replaced. If the bulb is not burned
out, check the fuse. See
Fuses and
Circuit Breakers on page 10-35.
Fog Lamps
If equipped with fog lamps, the
button is on the exterior lamp
control, left of the steering wheel.

Black plate (7,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Lighting 6-7
Exit Lighting
The headlamps, taillamps, back-up
lamps, parking lamps, and license
plate lamps come on at night, or in
areas with limited lighting, when the
key is removed from the ignition.
The dome lamps also come on
when the key is removed from the
ignition. The exterior lamps and
dome lamps remain on after the
door is closed for a set amount of
time, then automatically turn off.
If equipped with Keyless Access,
the exterior lamps and dome lamps
automatically turn on when the
driver door is opened after the
ignition is turned off. SeeIgnition
Positions (Key Access) on
page 9-15 orIgnition Positions
(Keyless Access) on page 9-16.
The exterior lamps turn off
immediately by turning the exterior
lamp control off.
This feature can be changed. See
Vehicle Personalization on
page 5-45.
Battery Load
Management
The vehicle has Electric Power
Management (EPM) that estimates
the battery's temperature and state
of charge. It then adjusts the voltage
for best performance and extended
life of the battery.
When the battery's state of charge
is low, the voltage is raised slightly
to quickly bring the charge back up.
When the state of charge is high,
the voltage is lowered slightly to
prevent overcharging. If the vehicle
has a voltmeter gauge or a voltage
display on the Driver Information
Center (DIC), you may see the
voltage move up or down. This is
normal. If there is a problem, an
alert will be displayed.
The battery can be discharged at
idle if the electrical loads are very
high. This is true for all vehicles.
This is because the generator
(alternator) may not be spinning fast enough at idle to produce all of the
power needed for very high
electrical loads.
A high electrical load occurs when
several of the following are on, such
as: headlamps, high beams, fog
lamps, rear window defogger,
climate control fan at high speed,
heated seats, engine cooling fans,
trailer loads, and loads plugged into
accessory power outlets.
EPM works to prevent excessive
discharge of the battery. It does this
by balancing the generator's output
and the vehicle's electrical needs.
It can increase engine idle speed to
generate more power whenever
needed. It can temporarily reduce
the power demands of some
accessories.
Normally, these actions occur in
steps or levels, without being
noticeable. In rare cases at the
highest levels of corrective action,
this action may be noticeable to the
driver. If so, a DIC message might
be displayed and it is recommended

Black plate (18,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
9-18 Driving and Operating
ACC/ACCESSORY (Amber
Indicator 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 Indicator
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 9-18. 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.
Starting the Engine
Move the shift lever to P (Park) or
N (Neutral). To restart the engine
when the vehicle is already moving,
use N (Neutral) only.
{Caution
Do not try to shift to P (Park) if the
vehicle is moving. If you do, you
could damage the transmission.
Shift to P (Park) only when the
vehicle is stopped.
{Caution
If you add electrical parts or
accessories, you could change
the way the engine operates. Any
resulting damage would not be
covered by the vehicle warranty.
See
Add-On Electrical Equipment
on page 9-68.

Black plate (31,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Driving and Operating 9-31
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 vehiclesuddenly 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 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.
Parking Brake
The Electric Parking Brake (EPB)
switch is on 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 when the engine
is not running.
The system has a red parking brake
status light and an amber parking
brake warning light. See
Electric
Parking Brake Light on page 5-20
and Service Electric Parking Brake
Light on page 5-20. There are also

Black plate (36,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
9-36 Driving and Operating
To turn TCS and StabiliTrak on
again, press and release the
g
button. The traction off lightiand
StabiliTrak OFF light
gin the
instrument cluster turn off.
Adding accessories can affect the
vehicle performance. See
Accessories and Modifications on
page 10-3.
Limited-Slip Differential
Vehicles with a limited-slip
differential can give more traction on
snow, mud, ice, sand, or gravel.
It works like a standard differential
most of the time, but when traction
is low, this feature allows the drive
wheel with the most traction to
move the vehicle.
Selective Ride Control
The vehicle may have a ride control
system called Selective Ride
Control. The system provides the
following performance benefits:
.Reduced Impact Harshness
.Improved Road Isolation
.Improved High-Speed Stability
.Improved Handling Response
.Better Control of Body Ride
Motions
To switch from TOUR to SPORT
mode, move the shift lever to the
M/S (Manual/Sport) position. TOUR:
Use for normal city and
highway driving. This setting
provides a smooth, soft ride.
SPORT: Use where road conditions
or personal preference demand
more control. This setting provides
more “feel,” or response to road
conditions through increased
steering effort and suspension
tuning.
The setting can be changed at any
time. Based on road conditions,
steering wheel angle, and vehicle
speed, the system automatically
adjusts to provide the best handling
while providing a smooth ride. The
TOUR and SPORT modes will feel
similar on a smooth road.

Black plate (40,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
9-40 Driving and Operating
{Warning
ACC has limited braking ability
and may not have time to slow
the vehicle down enough to avoid
a collision with another vehicle
you are following. This can occur
when vehicles suddenly slow or
stop ahead, or enter your lane.
Also see“Alerting the Driver” in
this section. Complete attention is
always required while driving and
you should be ready to take
action and apply the brakes. See
Defensive Driving on page 9-3.
{Warning
Adaptive Cruise Control will not
detect or brake for children,
pedestrians, animals, or other
objects.
(Continued)
Warning (Continued)
Do not use Adaptive Cruise
Control when:
.On winding and hilly roads or
when the sensors are
blocked by snow, ice, or dirt.
The system may not detect a
vehicle ahead. Keep the
entire front of the vehicle
clean.
.Visibility is low, such as in
fog, rain, or snow conditions.
Adaptive Cruise Control
performance is limited under
these conditions.
.On slippery roads where fast
changes in tire traction can
cause excessive wheel slip.
](On/Off):Press to turn the
system on or off. The indicator turns
white on the instrument cluster
when ACC is turned on.
RES+ (Resume/Accelerate):
Press the control up briefly to make
the vehicle resume to a previously
set speed, or hold upwards to
accelerate. If cruise control is
already active, use to increase
vehicle speed.

Black plate (42,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
9-42 Driving and Operating
When the accelerator pedal is
pressed, ACC will not brake
because it is overridden.
A warning message will appear
on the Driver Information Center
(DIC) and Head-Up Display
(HUD). SeeCruise Control
Messages on page 5-36.
.Press and hold RES+ up until
the desired set speed appears
on the display, then release it.
.To increase vehicle speed in
small increments, briefly press
RES+. For each press, the
vehicle increase to the next
5 km/h (1 mph) mark on the
speedometer.
When it is determined that there is
no vehicle ahead or the vehicle
ahead is beyond the selected
following gap, then the vehicle
speed will increase to the set speed.
The speedometer reading can be
displayed in either English or metric
units. See Instrument Cluster on
page 5-8. The increment value used
depends on the units displayed. Reducing Speed While ACC is at a
Set Speed
If ACC is already activated, do one
of the following:
.Use the brake to get to the
desired lower speed. Press
SET–
down and release the
accelerator pedal. The vehicle
will now cruise at the lower
speed.
.Press and hold SET– down until
the desired lower speed is
reached, then release it.
.To decrease the vehicle speed in
smaller increments, press SET−
down briefly. For each press, the
vehicle speed decreases to the
next 5 km/h (1 mph) mark on the
speedometer.
The speedometer reading can be
displayed in either English or metric
units. See Instrument Cluster on
page 5-8. The increment value used
depends on the units displayed. Selecting the Follow Distance Gap
When a slower moving vehicle is
detected ahead within the selected
following gap, ACC will adjust the
vehicle's speed and attempt to
maintain the follow distance gap
selected.
Press
3on the steering wheel to
adjust the following gap. Each press
cycles the gap button through three
settings: Far, Medium, or Near.
When pressed, the current gap
setting displays briefly on the
instrument cluster and HUD. The
gap setting will be maintained until it
is changed.
Since each gap setting corresponds
to a following time (Far, Medium,
or Near), the following distance will
vary based on vehicle speed. The
faster the vehicle speed, the further
back your vehicle will follow a
vehicle detected ahead. Consider
traffic and weather conditions when
selecting the following gap. The

Black plate (43,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Driving and Operating 9-43
range of selectable gaps may not be
appropriate for all drivers and
driving conditions.
Changing the gap setting
automatically changes the alert
timing sensitivity (Far, Medium,
or Near) for the Forward Collision
Alert (FCA) feature. SeeForward
Collision Alert (FCA) System on
page 9-50.
Alerting the Driver
If ACC is engaged, driver action
may be required when ACC cannot
apply sufficient braking because of
approaching a vehicle too rapidly.
When this condition occurs, the
collision alert symbol on the HUD
will flash on the windshield. Either
eight beeps will sound from the
front, or both sides of the Safety Alert Seat will pulse five times. See
“Collision/Detection Systems”
under
Vehicle Personalization on
page 5-45.
See Defensive Driving on page 9-3.
Approaching and Following a
Vehicle
The vehicle ahead symbol is in the
instrument cluster and HUD display.
The vehicle ahead symbol only
displays when a vehicle is detected
in your vehicle’s path moving in the
same direction.
If this symbol is not displaying, ACC
will not respond to or brake to
vehicles ahead.
ACC automatically slows the vehicle
down and adjusts vehicle speed to
follow the vehicle in front at the selected follow gap. The vehicle
speed increases or decreases to
follow the vehicle in front of you, but
will not exceed the set speed. It may
apply limited braking, if necessary.
When braking is active, the brake
lights will come on. The automatic
braking may feel or sound different
than if the brakes were applied
manually. This is normal.
Stationary or Very Slow-Moving
Objects
{Warning
Adaptive Cruise Control (ACC)
may not detect and react to
stopped or slow-moving vehicles
ahead of you. For example, the
system may not brake for a
vehicle it has never detected
moving. This can occur in
stop-and-go traffic or when a
vehicle suddenly appears due to
a vehicle ahead changing lanes.
Your vehicle may not stop and
(Continued)