ignition BUICK LACROSSE 2016 Repair Manual

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9159288) - 2016 - CRC - 10/5/15
204 Driving and Operating
Do Not Use ACC on Hills and
When Towing a Trailer
Do 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
]. 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 0304.
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 0165.
(Continued)

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9159288) - 2016 - CRC - 10/5/15
226 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . . . . . 227
California Proposition65 Warning . . . . . . . . . . . . . . . . . 227
California Perchlorate Materials Requirements . . . . . 228
Accessories and Modifications . . . . . . . . . . . . . . . . 228
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 229
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 230
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 231
Engine Oil . . . . . . . . . . . . . . . . . . . . 236
Engine Oil Life System . . . . . . . 238
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 239
Engine Air Cleaner/Filter . . . . . . 239
Cooling System . . . . . . . . . . . . . . 242
Engine Coolant . . . . . . . . . . . . . . . 243
Engine Overheating . . . . . . . . . . 245
Overheated Engine Protection Operating Mode . . . . . . . . . . . . . 246 Power Steering Fluid (2.4L L4
Engine and 3.6L V6 Engine
with FWD) . . . . . . . . . . . . . . . . . . 247
Power Steering Fluid (3.6L V6 Engine with AWD) . . . . . . . 247
Washer Fluid . . . . . . . . . . . . . . . . . 247
Brakes . . . . . . . . . . . . . . . . . . . . . . . 248
Brake Fluid . . . . . . . . . . . . . . . . . . . 249
Battery - North America . . . . . . 250
All-Wheel Drive . . . . . . . . . . . . . . . 251
Starter Switch Check . . . . . . . . . 251
Automatic Transmission Shift Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 252
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . . 252
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 252
Wiper Blade Replacement . . . . 253
Windshield Replacement . . . . . 253
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 254
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 254
Halogen Bulbs . . . . . . . . . . . . . . . . 254
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . 254
LED Lighting . . . . . . . . . . . . . . . . . 254 Headlamps, Front Turn Signal
and Parking Lamps . . . . . . . . . 255
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 256
License Plate Lamp . . . . . . . . . . 256
Replacement Bulbs . . . . . . . . . . . 257
Electrical System
High Voltage Devices and Wiring . . . . . . . . . . . . . . . . . . . . . . . 257
Electrical System Overload . . . 257
Fuses and Circuit Breakers . . . 258
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 259
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 262
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 264
All-Season Tires . . . . . . . . . . . . . . 265
Winter Tires . . . . . . . . . . . . . . . . . . 265
Summer Tires . . . . . . . . . . . . . . . . 265
Tire Sidewall Labeling . . . . . . . . 266
Tire Designations . . . . . . . . . . . . . 268
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . 268
Tire Pressure . . . . . . . . . . . . . . . . . 271
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . 272

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9159288) - 2016 - CRC - 10/5/15
252 Vehicle Care
Do not use the accelerator
pedal, and be ready to turn off
the engine immediately if it
starts.
3. Try to start the engine in each gear. The vehicle should start
only in P (Park) or N (Neutral).
If the vehicle starts in any other
position, contact your dealer for
service.
Automatic Transmission
Shift Lock Control
Function Check
{Warning
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle. It should be
parked on a level surface. 2. Apply the parking brake. Be
ready to apply the regular
brake immediately if the vehicle
begins to move.
3. With the engine off, turn the ignition on, but do not start the
engine. Without applying the
regular brake, try to move the
shift lever out of P (Park) with
normal effort. If the shift lever
moves out of P (Park), contact
your dealer for service.
Ignition Transmission
Lock Check
If equipped with a key type ignition,
while parked and with the parking
brake set, try to turn the ignition to
LOCK/OFF in each shift lever
position.
.The ignition should turn to
LOCK/OFF only when the shift
lever is in P (Park).
. The ignition key should come
out only in LOCK/OFF.
Contact your dealer if service is
required.
Park Brake and P (Park)
Mechanism Check
{Warning
When you are doing this check,
the vehicle could begin to move.
You or others could be injured
and property could be damaged.
Make sure there is room in front
of the vehicle in case it begins to
roll. Be ready to apply the regular
brake at once should the vehicle
begin to move.
Park on a fairly steep hill, with the
vehicle facing downhill. Keeping
your foot on the regular brake, set
the parking brake.
. To check the parking brake's
holding ability: With the engine
running and the transmission in
N (Neutral), slowly remove foot
pressure from the regular brake
pedal. Do this until the vehicle is
held by the parking brake only.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9159288) - 2016 - CRC - 10/5/15
Vehicle Care 259
Engine Compartment
Fuse Block
To remove the fuse block cover,
squeeze the three retaining clips on
the cover and lift it straight up.
Caution
Spilling liquid on any electrical
component on the vehicle may
damage it. Always keep the
covers on any electrical
component.
The vehicle may not be equipped
with all of the fuses, relays, and
features shown.Fuses Usage
1 Transmission control module–battery
2 Engine control module battery
3 A/C clutch Fuses Usage
5 Engine control module/Run/Crank
6 Wiper
7 Long range radar/ Front camera
8 Ignition coils–even (6–cylinder engine)/
Ignition coils–all
(4–cylinder engine)

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9159288) - 2016 - CRC - 10/5/15
260 Vehicle Care
FusesUsage
9 Ignition coils–odd (6–cylinder engine)
10 Engine control module–switched
battery
11 6–cylinder Engine: post catalytic
converter/O2 sensor/
Heater/Mass air flow
sensor/FlexFuel
sensor/Secondary
air induction
solenoid
12 Starter
13 Crank for transmission control
module/Fuel pump
power/Chassis
control module
(eAssist)
14 Cabin heater coolant pump (eAssist)/
secondary air
injector/Secondary
air injector with
pressure sensor Fuses
Usage
15 Motor generator unit coolant pump
(eAssist)
16 Run/Crank for eAssist power
inverter module
17 –
18 Sunshade module/ Vehicle air
purification system/
Ventilated seats
20 Heated steering wheel (non eAssist)
21 Rear power windows
22 Sunroof
23 Variable effort steering (if
equipped) or eAssist
power inverter
module
24 Front power windows
25 Rear heated seats Fuses
Usage
26 Antilock brake system pump
27 Electric parking brake
28 Rear window defogger
29 Heated seat/Left power lumbar
30 Heated Seat/Right power pack cooling
fan (eAssist)
31 AWD/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
37 Right high-beam

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 263
The vehicle may not be equipped
with all of the fuses, relays, and
features shown.Fuses Usage
1 APO 3
2 Body control module 7
3 Steering wheel controls backlight
4 Radio/Human machine interface/
Rear auxiliary audio
jack/Front auxiliary
audio video jack/
Touchpad/Remote
media player/Bluray
remote media player
5 OnStar/Universal hands–free phone
6 Power outlet 1
7 Power outlet 2
8 Body control module 1
9 Body control module 4 Fuses Usage
10 Body control module 8
11 Front HVAC/Blower
12 Passenger seat
13 Driver seat
14 Diagnostic link connector
15 Airbag/Automatic occupant sensing
16 Trunk
17 HVAC Controller
18 Pre-fuse for fuses 4 and 5
19 Center stack displays/Head-up
display/Right
steering wheel
control switch/Rear
seat infotainment
display (eAssist)/
HVAC/Center stack
displays Fuses Usage
20 Rear seat entertainment
display/Rear seat
audio
21 Instrument cluster
22 Discrete logic ignition switch
23 Body control module 3
24 Body control module 2
25 Rear HVAC/Blower
26 AC DC inverter
Relays Usage R1 Trunk relay
R2 –
R3 Power outlet relay

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9159288) - 2016 - CRC - 10/5/15
274 Vehicle Care
alternate tires and wheels allow the
TPMS to continue to function
properly.
SeeTire Pressure Monitor
Operation 0274.
See Radio Frequency
Statement 0341.
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 0171.
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) 0123. 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
they are cold. See
Vehicle Load
Limits 0171, for an example of the
Tire and Loading Information label
and its location. Also see Tire
Pressure 0271.
The TPMS can warn about a low
tire pressure condition but it does
not replace normal tire
maintenance. See Tire Inspection
0 277, Tire Rotation 0277 and
Tires 0264.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 275
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.
Factory-installed Tire Inflator Kits
use a GM-approved liquid tire
sealant. Using non-approved tire
sealants could damage the TPMS
sensors. See Tire Sealant and
Compressor Kit 0285 for
information regarding the inflator kit
materials and instructions.
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 0279.
. 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.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9159288) - 2016 - CRC - 10/5/15
276 Vehicle Care
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. Turn the ignition to ON/RUN with the engine off or place the
vehicle power mode in ON/
RUN/START. See Ignition
Positions (Keyless Access)
0 175 orIgnition Positions (Key
Access) 0176.
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) 0123.
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

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 277
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.
Tire Inspection
We recommend that the tires,
including the spare tire, if the
vehicle has one, be inspected
for signs of wear or damage at
least once a month.
Replace the tire if:
.The indicators at three or
more places around the tire
can be seen.
.There is cord or fabric
showing through the tire's
rubber.
.The tread or sidewall is
cracked, cut, or snagged
deep enough to show cord or
fabric.
.The tire has a bump, bulge,
or split.
.The tire has a puncture, cut,
or other damage that cannot
be repaired well because of
the size or location of the
damage.
Tire Rotation
Tires should be rotated every
12 000 km (7,500 mi). See
Maintenance Schedule 0314.
Tires are rotated to achieve a
more uniform wear for all tires.
The first rotation is the most
important. Anytime unusual wear is
noticed, rotate the tires as soon
as possible, check for proper tire
inflation pressure, and check for
damaged tires or wheels. If the
unusual wear continues after the
rotation, check the wheel
alignment. See
When It Is Time
for New Tires 0278 andWheel
Replacement 0282.
Use this rotation pattern when
rotating the tires.