ignition BUICK LACROSSE 2017 Workshop Manual

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
Driving and Operating 187
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.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

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
188 Driving and Operating
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 isnormal, and is done to periodically
check the correct operation of the
EPB system.
If the EPB fails to apply, block the
rear wheels to prevent vehicle
movement.
EPB Release
To release the EPB:
1. Place the ignition in the ACC/ ACCESSORY or ON/RUN
position.
2. Apply and hold the brake pedal.
3. Press the EPB switch momentarily .
The EPB is released when the red
parking brake status light is off.
If the amber parking brake warning
light is on, release the EPB by
pressing and holding the EPB
switch. Continue to hold the switch
until the red parking brake status
light is off. If either light stays on
after release is attempted, see your
dealer.
Caution
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.
Brake Assist
The Brake Assist feature is
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

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
194 Driving and Operating
Increasing Speed While Using
Cruise Control
Do one of the following:
.Press and hold RES+ up until
the vehicle accelerates to the
desired speed, then release it.
. To increase vehicle speed in
small increments, press RES+
up briefly. For each press, the
vehicle goes about 1.6 km/h
(1 mph) faster.
Reducing Speed While Using
Cruise Control
Do one of the following:
. Press and hold SET− down until
the desired lower speed is
reached, then release it.
. To slow down in small
increments, press SET−down
briefly. For each press, the
vehicle goes about 1.6 km/h
(1 mph) slower. Passing Another Vehicle While
Using Cruise Control
Use the accelerator pedal to
increase the vehicle speed. When
you take your foot off the pedal, the
vehicle will slow down to the
previously set cruise speed. While
pressing the accelerator pedal or
shortly following the release to
override cruise control, briefly
pressing SET−
will result in cruise
set to the current vehicle speed.
Using Cruise Control on Hills
How well the cruise control will work
on hills depends upon the vehicle
speed, load, and the steepness of
the hills. When going up steep hills,
you might have to step on the
accelerator pedal to maintain your
speed. When going downhill, you
might have to brake or shift to a
lower gear to keep your speed
down. If the brake pedal is applied,
cruise control will disengage.
Ending Cruise Control
There are four ways to end cruise
control:
. Step lightly on the brake pedal. .
Press*.
. Shift the transmission to
N (Neutral).
. To turn off cruise control,
press
5.
Erasing Speed Memory
The cruise control set speed is
erased from memory if
5is pressed
or the ignition is turned off.
Adaptive Cruise Control
If equipped with Adaptive Cruise
Control (ACC), it allows for selecting
the cruise control set speed and
following gap. Read this entire
section before using this system.
ACC uses a radar sensor to detect
other vehicles. See Radio
Frequency Statement 0321. The
following gap is the following time
(or distance) between your vehicle
and a vehicle detected directly
ahead in your path, moving in the
same direction. If no vehicle is
detected in your path, ACC works
like regular cruise control.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
Driving and Operating 199
A message will appear on the DIC
indicating that cruise is disengaging.
The ACC active symbol will not be
displayed when ACC is no longer
active.
Notification to Resume ACC
ACC will maintain a following gap
behind a detected vehicle and slow
your vehicle to a stop behind that
vehicle.
If the stopped vehicle ahead has
driven away and ACC has not
resumed, the vehicle ahead
indicator will flash as a reminder to
check traffic ahead before
proceeding. In addition, the left and
right sides of the Safety Alert Seat
will pulse three times, or three
beeps will sound. See”Alert Type”
and “Go Notifier” in“Collision/
Detection Systems” underVehicle
Personalization 0138.
When the vehicle ahead drives
away, press RES+ or the
accelerator pedal to resume cruise
control. If stopped for more than
two minutes or if the driver door is
opened and the driver safety belt is unbuckled, ACC automatically
applies the Electric Parking Brake
(EPB) to hold the vehicle. The
Electric Parking Brake status light
will turn on. See
Electric Parking
Brake 0187. To resume ACC and
release the EPB, press the
accelerator pedal.
A DIC warning message may
display indicating to shift to P (Park)
before exiting the vehicle. See
Vehicle Messages 0128.
{Warning
If ACC has stopped the vehicle,
and if ACC is disengaged, turned
off, or canceled, the vehicle will
no longer be held at a stop. The
vehicle can move. When ACC is
holding the vehicle at a stop,
always be prepared to manually
apply the brakes.
{Warning
Leaving the vehicle without
placing it in P (Park) can be
dangerous. Do not leave the
vehicle while it is being held at a
stop by ACC. Always place the
vehicle in P (Park) and turn off
the ignition before leaving the
vehicle.
ACC Override
If using the accelerator pedal while
ACC is active, a DIC warning
message will indicate that automatic
braking will not occur. See Vehicle
Messages 0128. ACC will resume
operation when the accelerator
pedal is not being pressed.
{Warning
The ACC will not automatically
apply the brakes if your foot is
resting on the accelerator pedal.
You could crash into a vehicle
ahead of you.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
Driving and Operating 201
Other Vehicle Lane Changes
ACC will not detect a vehicle ahead
until it is completely in the lane. The
brakes may need to be manually
applied.Do Not Use ACC on Hills and
When Towing a TrailerDo not use ACC when driving on
steep hills or when towing a trailer.
ACC will not detect a vehicle in the
lane while driving on steep hills. The
driver will often need to take over
acceleration and braking on steep
hills, especially when towing a
trailer. If the brakes are applied, the
ACC disengages.Disengaging ACC
There are three ways to
disengage ACC:
.
Step lightly on the brake pedal.
. Press
*.
. Press
5.
Erasing Speed Memory
The cruise control set speed is
erased from memory if
5is pressed
or if the ignition is turned off.
Cleaning the Sensing System
The radar sensor on the front of the
vehicle can become blocked by
snow, ice, dirt, or mud. This area
needs to be cleaned for ACC to
operate properly.
For cleaning instructions, see
“Washing the Vehicle” under
Exterior Care 0286.
System operation may also be
limited under snow, heavy rain,
or road spray conditions.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
250 Vehicle Care
The vehicle may not be equipped
with all of the fuses, relays, and
features shown.Fuses Usage
1 –
2 –
3 ABS pump
5 AC DC inverter
6 Rear closure Fuses Usage
7 Left corner lamp
8 Power windows/ Rearview mirror/
Power seats
9 Engine boost
10 Semi-active damping system
11 DC DC Battery 1 Fuses Usage
12 Rear window defogger
13 Heated mirrors
14 –
15 Passive entry/ Passive start
16 Front wipers
17 Passenger power seat
18 ABS valve
19 Driver power seat
21 Sunroof
22 Right corner lamp
23 Auto headlamp leveling
24 –
26 Transmission control module/Ignition
27 Instrument panel/ Ignition
28 Electronic precision shift/Ignition

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
Vehicle Care 251
FusesUsage
29 Rear vision camera/ Ventilation
30 Malfunction indicator lamp/Shift solenoid
32 Canister vent solenoid
33 Front heated seats
34 Rear heated seat/ Vehicle body safety
module/Energy
storage system fan
35 Fog lamps
36 Fuel module
38 –
39 –
40 Steering columnn lock
41 –
43 Heated steering wheel
44 Headlamp leveling/ Rear seat ventilation
45 – Fuses
Usage
46 Engine control module/Ignition
47 –
48 Engine boost/Left cooling fan
49 DC DC battery 2/AWD
50 –
51 –
52 –
53 –
54 –
55 –
56 –
57 Transmission auxiliary pump
58 TRCM
59 High-beam headlamps
60 Cooling fan
61 –
62 – Fuses
Usage
63 –
65 A/C HEV
67 –
68 –
69 Right HID low-beam headlamps
70 Left HID low-beam headlamps
72 Starter pinion
74 Starter motor
75 Engine control module
76 Powertrain –off
engine
77 –
78 Horn
79 Washer pump
81 Transmission control module/ Engine
control module
82 –
83 Ignition coils

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
264 Vehicle Care
This sequence will continue upon
subsequent vehicle start-ups as
long as the malfunction exists.
When the malfunction indicator is
illuminated, the system may not be
able to detect or signal low tire
pressure as intended. TPMS
malfunctions may occur for a variety
of reasons, including the installation
of replacement or alternate tires or
wheels on the vehicle that prevent
the TPMS from functioning properly.
Always check the TPMS malfunction
telltale after replacing one or more
tires or wheels on your vehicle to
ensure that the replacement or
alternate tires and wheels allow the
TPMS to continue to function
properly.
SeeTire Pressure Monitor
Operation 0264.
See Radio Frequency Statement
0 321.Tire Pressure Monitor
Operation
This vehicle may have a Tire
Pressure Monitor System (TPMS).
The TPMS is designed to warn the
driver when a low tire pressure
condition exists. TPMS sensors are
mounted onto each tire and wheel
assembly, excluding the spare tire
and wheel assembly. The TPMS
sensors monitor the air pressure in
the tires and transmits the tire
pressure readings to a receiver
located in the vehicle.
When a low tire pressure condition
is detected, the TPMS illuminates
the low tire pressure warning light
located on the instrument cluster.
If the warning light comes on, stop
as soon as possible and inflate the
tires to the recommended pressure shown on the Tire and Loading
Information label. See
Vehicle Load
Limits 0170.
A message to check the pressure in
a specific tire displays in the Driver
Information Center (DIC). The low
tire pressure warning light and the
DIC warning message come on at
each ignition cycle until the tires are
inflated to the correct inflation
pressure. Using the DIC, tire
pressure levels can be viewed. For
additional information and details
about the DIC operation and
displays see Driver Information
Center (DIC) 0122.
The low tire pressure warning light
may come on in cool weather when
the vehicle is first started, and then
turn off as the vehicle is driven. This
could be an early indicator that the
air pressure is getting low and
needs to be inflated to the proper
pressure.
A Tire and Loading Information
label, attached to your vehicle,
shows the size of the original
equipment tires and the correct
inflation pressure for the tires when

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
Vehicle Care 265
they are cold. SeeVehicle Load
Limits 0170, for an example of the
Tire and Loading Information label
and its location. Also see Tire
Pressure 0261.
The TPMS can warn about a low
tire pressure condition but it does
not replace normal tire
maintenance. See Tire Inspection
0 267, Tire Rotation 0267 andTires
0 254.
Caution
Tire sealant materials are not all
the same. A non-approved tire
sealant could damage the TPMS
sensors. TPMS sensor damage
caused by using an incorrect tire
sealant is not covered by the
vehicle warranty. Always use only
the GM approved tire sealant
available through your dealer or
included in the vehicle.
TPMS Malfunction Light and
Message
The TPMS will not function properly
if one or more of the TPMS sensors
are missing or inoperable. When the
system detects a malfunction, the
low tire warning light flashes for
about one minute and then stays on
for the remainder of the ignition
cycle. A DIC warning message also
displays. The malfunction light and
DIC warning message come on at
each ignition cycle until the problem
is corrected. Some of the conditions
that can cause these to come
on are:
.
One of the road tires has been
replaced with the spare tire. The
spare tire does not have a
TPMS sensor. The malfunction
light and DIC message should
go off after the road tire is
replaced and the sensor
matching process is performed
successfully. See “TPMS Sensor
Matching Process” later in this
section. .
The TPMS sensor matching
process was not done or not
completed successfully after
rotating the tires. The
malfunction light and the DIC
message should go off after
successfully completing the
sensor matching process. See
"TPMS Sensor Matching
Process" later in this section.
. One or more TPMS sensors are
missing or damaged. The
malfunction light and the DIC
message should go off when the
TPMS sensors are installed and
the sensor matching process is
performed successfully. See
your dealer for service.
. Replacement tires or wheels do
not match the original equipment
tires or wheels. Tires and wheels
other than those recommended
could prevent the TPMS from
functioning properly. See Buying
New Tires 0269.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-9803782) -
2017 - crc - 9/7/16
266 Vehicle Care
.Operating electronic devices or
being near facilities using radio
wave frequencies similar to the
TPMS could cause the TPMS
sensors to malfunction.
If the TPMS is not functioning
properly it cannot detect or signal a
low tire condition. See your dealer
for service if the TPMS malfunction
light and DIC message comes on
and stays on.
TPMS Sensor Matching
Process
Each TPMS sensor has a unique
identification code. The identification
code needs to be matched to a new
tire/wheel position after rotating the
vehicle’s tires or replacing one or
more of the TPMS sensors. The
TPMS sensor matching process
should also be performed after
replacing a spare tire with a road
tire containing the TPMS sensor.
The malfunction light and the DIC
message should go off at the next
ignition cycle. The sensors are
matched to the tire/wheel positions,
using a TPMS relearn tool, in the
following order: driver side front tire, passenger side front tire, passenger
side rear tire, and driver side rear.
See your dealer for service or to
purchase a relearn tool. A TPMS
relearn tool can also be purchased.
See Tire Pressure Monitor Sensor
Activation Tool at
www.gmtoolsandequipment.com or
call 1-800-GM TOOLS
(1-800-468-6657).
There are two minutes to match the
first tire/wheel position, and
five minutes overall to match all four
tire/wheel positions. If it takes
longer, the matching process stops
and must be restarted.
The TPMS sensor matching
process is:
1. Set the parking brake.
2. Place the vehicle in ON/RUN/ START. See Ignition Positions
0 173.
3. Make sure the Tire Pressure info page option is turned on.
The info pages on the DIC can
be turned on and off through
the Settings menu. See Driver
Information Center (DIC) 0122. 4. Use the DIC controls on the
right side of the steering wheel
to scroll to the Tire Pressure
screen under the DIC
info page.
5. Press and hold
Vin the center
of the DIC controls.
The horn sounds twice to
signal the receiver is in relearn
mode and the TIRE
LEARNING ACTIVE message
displays on the DIC screen.
6. Start with the driver side front tire.
7. Place the relearn tool against the tire sidewall, near the valve
stem. Then press the button to
activate the TPMS sensor.
A horn chirp confirms that the
sensor identification code has
been matched to this tire and
wheel position.
8. Proceed to the passenger side front tire, and repeat the
procedure in Step 7.
9. Proceed to the passenger side rear tire, and repeat the
procedure in Step 7.