2015 BUICK LACROSSE brake sensor

Black plate (47,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Driving and Operating 9-47
Disengaging ACC
There are three ways to
disengage ACC:
.Step lightly on the brake pedal.
.Press*.
.Press].
Erasing Speed Memory
The cruise control set speed is
erased from memory if
]is
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 on page 10-85.
System operation may also be
limited under snow, heavy rain,
or road spray conditions.
Driver Assistance
Systems
This vehicle may have features that
work together to help avoid crashes
or reduce crash damage while
driving, backing, and parking. Read
this entire section before using
these systems.
{Warning
Do not rely on the Driver
Assistance Systems. These
systems do not replace the need
for paying attention and driving
safely. You may not hear or feel
alerts or warnings provided by
these systems. Failure to use
proper care when driving may
result in injury, death, or vehicle
damage. See Defensive Driving
on page 9-3.
Under many conditions, these
systems will not:
(Continued)
Warning (Continued)
.Detect children, pedestrians,
bicyclists, or animals.
.Detect vehicles or objects
outside the area monitored by
the system.
.Work at all driving speeds.
.Warn you or provide you with
enough time to avoid a crash.
.Work under poor visibility or
bad weather conditions.
.Work if the detection sensor
is not cleaned or is covered
by ice, snow, mud, or dirt.
Complete attention is always
required while driving, and you
should be ready to take action
and apply the brakes and/or steer
the vehicle to avoid crashes.

Black plate (51,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Driving and Operating 9-51
FCA detects vehicles within a
distance of approximately 60 m
(197 ft) and operates at speeds
above 40 km/h (25 mph). If the
vehicle has Adaptive Cruise Control
(ACC), it can detect vehicles to
distances of approximately 110 m
(360 ft). SeeAdaptive Cruise
Control on page 9-39.
{Warning
FCA is a warning system and
does not apply the brakes. When
approaching a slower-moving or
stopped vehicle ahead too rapidly,
or when following a vehicle too
closely, FCA may not provide a
warning with enough time to help
avoid a crash. FCA does not warn
of pedestrians, animals, signs,
guardrails, bridges, construction
barrels, or other objects. Be ready
to take action and apply the
brakes. For more information, see
Defensive Driving on page 9-3. FCA can be disabled through
vehicle personalization. See the
“Auto Collision Preparation”
portion
of “Collision/Detection Systems”
under Vehicle Personalization on
page 5-45.
Detecting the Vehicle Ahead
FCA warnings will not occur unless
the FCA system detects a vehicle
ahead. The vehicle-ahead indicator
will display green when a vehicle is
detected in front. Vehicles may not
be detected on curves, highway exit
ramps, or hills; or due to poor
visibility. FCA will not detect another
vehicle ahead until it is completely
in the driving lane.
{Warning
FCA does not provide a warning
to help avoid a crash, unless it
detects a vehicle. FCA may not
detect a vehicle ahead if the FCA
sensor is blocked by dirt, snow,
or ice, or if the windshield is
damaged. It may also not detect a
vehicle on winding or hilly roads,
or in conditions that can limit
visibility such as fog, rain,
or snow, or if the headlamps or
windshield are not cleaned or in
proper condition. Keep the
windshield, headlamps, and FCA
sensors clean and in good repair.

Black plate (53,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Driving and Operating 9-53
Active Emergency
Braking System
If the vehicle has Adaptive Cruise
Control (ACC) it also has the Active
Emergency Braking System, which
includes Intelligent Brake
Assist (IBA) and the Automatic
Collision Preparation (ACP) System.
These systems can provide a boost
to braking or automatically brake the
vehicle to help avoid or lessen the
severity of crashes when driving in a
forward gear.
Intelligent Brake Assist (IBA)
IBA may activate when the brake
pedal is applied quickly by providing
a boost to braking based on the
speed of approach and distance to
a vehicle ahead.
Minor brake pedal pulsations or
pedal movement during this time is
normal and the brake pedal should
continue to be applied as needed.
IBA will automatically disengage
only when the brake pedal is
released.
{Warning
IBA may increase vehicle braking
in situations when it may not be
necessary. You could block the
flow of traffic. If this occurs, take
your foot off the brake pedal and
then apply the brakes as needed.
Automatic Collision
Preparation (ACP) System
When driving in a forward gear
above 9 km/h (5 mph), ACP may
help reduce crash damage by
applying the brakes. It has a
detection range of approximately
60 m (197 ft). This front automatic
braking can only occur if a vehicle is
detected. This is shown by the FCA
vehicle ahead indicator being lit.
SeeForward Collision Alert (FCA)
System on page 9-50.
{Warning
ACP is an emergency crash
preparation feature and is not
designed to avoid crashes. Do
not rely on ACP to brake the
vehicle.
ACP may not:
.Respond to stopped vehicles,
pedestrians, or animals.
.Detect a vehicle ahead on
winding or hilly roads.
.Detect a stopped or
slow-moving vehicle or other
object ahead.
.Detect a vehicle when
weather limits visibility, such
as in fog, rain, or snow. In
these situations, ACP sensor
performance is limited.
(Continued)

Black plate (37,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Vehicle Care 10-37
J-CaseFuses Usage
25 Rear Heated Seats
26 Antilock Brake System Pump
27 Electric Parking Brake
28 Rear Window Defogger
41 Brake Vacuum Pump
42 Cooling Fan K2
43 Not Used
44 Transmission Auxiliary Oil Pump
(eAssist)
45 Cooling Fan K1
59 AIR Pump Mini Fuses Usage
1 Transmission Control Module —
Battery
2 Engine Control Module Battery
3 Air Conditioning Compressor Clutch
5 Engine Control Module Run/Crank
7 Long Range Radar/ Front Camera
8 Ignition Coils –Even
(Six Cylinder
Engine), Ignition
Coils –All (Four
Cylinder Engine)
9 Ignition Coils –Odd
(Six Cylinder
Engine) Mini Fuses Usage
10 Engine Control Module–Switched
Battery (from Engine
Control Module
Relay)
11 Six Cylinder Engine: Post Catalytic
Converter Oxygen
Sensor Heater,
Mass Air Flow
Sensor, FlexFuel
Sensor, Secondary
Air Induction
Solenoid
13 Crank for Transmission
Control Module/Fuel
Pump Power/
Chassis Control
Module (eAssist)

Black plate (38,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
10-38 Vehicle Care
Mini Fuses Usage14 Cabin Heater Coolant Pump
(eAssist)/Secondary
Air Injector/
Secondary Air
Injector with
Pressure Sensor
15 Motor Generator Unit Coolant Pump
(eAssist)
16 Run/Crank for eAssist Power
Inverter Module
17 Not Used
18 Sunshade Module, Vehicle Air
Purification System,
Ventilated Seats
20 Heated Steering Wheel (non eAssist) Mini Fuses Usage
23 Variable Effort Steering (if
equipped) or eAssist
Power Inverter
Module
29 Heated Seat, Left/ Power Lumbar
30 Heated Seat, Right/ Power Pack Cooling
Fan (eAssist)
31 All-Wheel Drive, Electronic
Suspension Control
32 Body Control Module 6
33 Memory Seat –
Front
34 Antilock Brake System Valves
35 Amplifier
36 Adaptive Forward Lighting (AFL)
Motors–Battery Mini Fuses Usage
37 Right High Beam
38 Left High Beam
46 Cooling Fan Relay
47 Six Cylinder Engine: Pre Catalytic
Converter Oxygen
Sensor Heater,
Canister Purge
Solenoid. Four
Cylinder Engine: Pre
and Post Catalytic
Converter Oxygen
Sensor Heaters,
Canister Purge
Solenoid
48 Fog Lamps
49 Right High Intensity Discharge
Headlamp
50 Left High Intensity Discharge
Headlamp
51 Horn

Black plate (55,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Vehicle Care 10-55
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. Turn the ignition to ON/RUN withthe engine off or place the
vehicle power mode in ON/RUN/
START. See Ignition Positions
(Key Access) on page 9-15 or
Ignition Positions (Keyless
Access) on page 9-16.
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) on
page 5-28.
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 the
V(Set/
Reset) button located in 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.
10. Proceed to the driver side rear tire, and repeat the procedure
in Step 7. The horn sounds two
times to indicate the sensor
identification code has been
matched to the driver side rear
tire, and the TPMS sensor
matching process is no longer
active. The TIRE LEARNING
ACTIVE message on the DIC
display screen goes off.
11. Turn the ignition to LOCK/OFF or press STOP to turn the
ignition off.
12. Set all four tires to the recommended air pressure
level as indicated on the Tire
and Loading Information label.

Black plate (62,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
10-62 Vehicle Care
overloaded. Excessive speed,
underinflation, or excessive
loading, either separately or in
combination, can cause heat
buildup and possible tire failure.
Wheel Alignment and Tire
Balance
The tires and wheels were aligned
and balanced at the factory to
provide the longest tire life and best
overall performance. Adjustments to
wheel alignment and tire balancing
are not necessary on a regular
basis. Consider an alignment check
if there is unusual tire wear or the
vehicle is significantly pulling to one
side or the other. Some slight pull to
the left or right, depending on the
crown of the road and/or other road
surface variations such as troughs
or ruts, is normal. If the vehicle is
vibrating when driving on a smooth
road, the tires and wheels may need
to be rebalanced. See your dealer
for proper diagnosis.
Wheel Replacement
Replace any wheel that is bent,
cracked, or badly rusted or
corroded. If wheel nuts keep coming
loose, the wheel, wheel bolts, and
wheel nuts should be replaced.
If the wheel leaks air, replace it.
Some aluminum wheels can be
repaired. See your dealer if any of
these conditions exist.
Your dealer will know the kind of
wheel that is needed.
Each new wheel should have the
same load-carrying capacity,
diameter, width, offset, and be
mounted the same way as the one it
replaces.
Replace wheels, wheel bolts, wheel
nuts, or Tire Pressure Monitor
System (TPMS) sensors with new
GM original equipment parts.{Warning
Using the wrong replacement
wheels, wheel bolts, or wheel
nuts can be dangerous. It could
affect the braking and handling of
the vehicle. Tires can lose air,
and cause loss of control, causing
a crash. Always use the correct
wheel, wheel bolts, and wheel
nuts for replacement.
{Caution
The wrong wheel can also cause
problems with bearing life, brake
cooling, speedometer or
odometer calibration, headlamp
aim, bumper height, vehicle
ground clearance, and tire or tire
chain clearance to the body and
chassis.