2018 BUICK LACROSSE Owner's Manual

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
256 Vehicle Care
FusesUsage
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 –
63 –
65 A/C HEV Fuses
Usage
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
84 Coil Fuses
Usage
85 Engine control module switch 2
86 Engine control module switch 1
87 SAI reaction pump
88 Aeroshutter
89 Headlamp washer
91 –
92 TPIM motor generator unit pump
93 Headlamp leveling
95 SAI reaction solenoid
96 Fuel heater
97 –
99 Coolant pump
Relays Usage
4 AC DC inverter
20 Rear defogger
25 Front wiper control
31 Run/Crank

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
Vehicle Care 257
RelaysUsage
37 Front wiper speed
42 Transmission auxiliary pump
64 A/C control
66 Powertrain
71 HID low-beam headlamps
73 Starter motor
80 Starter pinion
90 SAI reaction solenoid
94 Headlamp washer
98 SAI reaction pumpInstrument Panel Fuse
Block
The instrument panel fuse block is
in the instrument panel, on the
driver side of the vehicle. To operate
the fuses, open the fuse panel by
pulling down at the top.
Pull the panel toward you to release
it from the hinges.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
258 Vehicle Care
The vehicle may not be equipped
with all of the fuses, relays, and
features shown.Fuses Usage
F1 Left window
F2 Right window
F3 –
F4 HVAC blower
F5 Battery 2 Fuses
Usage
F6 Electric steering column
F7 –
F8 Battery 3
F9 Engine control module/Battery
F10 Body control module 2 On/Off Fuses
Usage
F11 –
F12 –
F13 –
F14 –
F15 Transmission control module On/Off
F16 Amplifier
F17 –
F18 Battery 7
F19 –
F20 Battery 1
F21 Battery 4
F22 Battery 6
F23 Electric steering column lock
F24 Airbag sensing diagnostic module/
Passenger sensing
module
F25 Diagnostic link
F26 –
F27 AC DC inverter

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
Vehicle Care 259
FusesUsage
F28 –
F29 Body control module 8
F30 Overhead console
F31 Steering wheel control
F32 –
F33 HVAC
F34 Center gateway module
F35 Integrated chassis control module
F36 Charger
F37 Auxiliary power outlet/Cigar lighter
F38 OnStar
F39 Monitor
F40 Object detection
F41 Body control module 1 On/Off
F42 Radio Fuses
Usage
F43 Rear accessory power outlet
F44 Front accessory power outlet
Relays Usage
K1 –
K2 Retained accessory power
K3 –
K4 –
K5 LogisticsWheels and Tires
Tires
Every new GM vehicle has
high-quality tires made by a
leading tire manufacturer. See
the warranty manual for
information regarding the tire
warranty and where to get
service. For additional
information refer to the tire
manufacturer.
{Warning
.Poorly maintained and
improperly used tires are
dangerous.
.Overloading the tires can
cause overheating as a
result of too much
flexing. There could be a
blowout and a serious
crash. See Vehicle Load
Limits 0166.
(Continued)

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
260 Vehicle Care
Warning (Continued)
.Underinflated tires pose
the same danger as
overloaded tires. The
resulting crash could
cause serious injury.
Check all tires frequently
to maintain the
recommended pressure.
Tire pressure should be
checked when the tires
are cold.
.Overinflated tires are
more likely to be cut,
punctured, or broken by
a sudden impact—such
as when hitting a pothole.
Keep tires at the
recommended pressure.
.Worn or old tires can
cause a crash. If the
tread is badly worn,
replace them.
(Continued)
Warning (Continued)
.Replace any tires that
have been damaged by
impacts with potholes,
curbs, etc.
.Improperly repaired tires
can cause a crash. Only
the dealer or an
authorized tire service
center should repair,
replace, dismount, and
mount the tires.
.Do not spin the tires in
excess of 56 km/h
(35 mph) on slippery
surfaces such as snow,
mud, ice, etc. Excessive
spinning may cause the
tires to explode.
All-Season Tires
This vehicle may come with
all-season tires. These tires are
designed to provide good overall
performance on most road surfaces and weather conditions. Original
equipment tires designed to GM's
specific tire performance criteria
have a TPC specification code
molded onto the sidewall. Original
equipment all-season tires can be
identified by the last two characters
of this TPC code, which will
be
“MS.”
Consider installing winter tires on
the vehicle if frequent driving on
snow or ice-covered roads is
expected. All-season tires provide
adequate performance for most
winter driving conditions, but they
may not offer the same level of
traction or performance as winter
tires on snow or ice-covered roads.
See Winter Tires 0260.
Winter Tires
This vehicle was not originally
equipped with winter tires. Winter
tires are designed for increased
traction on snow and ice-covered
roads. Consider installing winter
tires on the vehicle if frequent
driving on ice or snow covered
roads is expected. See your dealer

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
Vehicle Care 261
for details regarding winter tire
availability and proper tire selection.
Also, seeBuying New Tires 0274.
With winter tires, there may be
decreased dry road traction,
increased road noise, and shorter
tread life. After changing to winter
tires, be alert for changes in vehicle
handling and braking.
If using winter tires:
. Use tires of the same brand and
tread type on all four wheel
positions.
. Use only radial ply tires of the
same size, load range, and
speed rating as the original
equipment tires.
Winter tires with the same speed
rating as the original equipment tires
may not be available for H, V, W, Y,
and ZR speed rated tires. If winter
tires with a lower speed rating are
chosen, never exceed the tire's
maximum speed capability.Tire Sidewall Labeling
Useful information about a tire is
molded into its sidewall. The
examples show a typical
passenger vehicle tire and a
compact spare tire sidewall.
Passenger (P-Metric) Tire Example
(1) Tire Size:The tire size is a
combination of letters and
numbers used to define a
particular tire's width, height,
aspect ratio, construction type,
and service description. See the
“Tire Size” illustration later in this
section. (2) TPC Spec (Tire
Performance Criteria
Specification)
:Original
equipment tires designed to
GM's specific tire performance
criteria have a TPC specification
code molded onto the sidewall.
GM's TPC specifications meet or
exceed all federal safety
guidelines.
(3) DOT (Department of
Transportation)
:The
Department of Transportation
(DOT) code indicates that the
tire is in compliance with the
U.S. Department of
Transportation Motor Vehicle
Safety Standards.
DOT Tire Date of
Manufacture
:The last four
digits of the TIN indicate the tire
manufactured date. The first two
digits represent the week (01–
52) and the last two digits, the
year. For example, the third

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
262 Vehicle Care
week of the year 2010 would
have a four-digit DOT date
of 0310.
(4) Tire Identification Number
(TIN)
:The letters and numbers
following the DOT (Department
of Transportation) code are the
Tire Identification Number (TIN).
The TIN shows the
manufacturer and plant code,
tire size, and date the tire was
manufactured. The TIN is
molded onto both sides of the
tire, although only one side may
have the date of manufacture.
(5) Tire Ply Material
:The type
of cord and number of plies in
the sidewall and under the tread.
(6) Uniform Tire Quality
Grading (UTQG)
:Tire
manufacturers are required to
grade tires based on three
performance factors: treadwear,
traction, and temperature
resistance. For more information
see Uniform Tire Quality
Grading 0276. (7) Maximum Cold Inflation
Load Limit
:Maximum load that
can be carried and the
maximum pressure needed to
support that load.
Compact Spare Tire Example
(1) Tire Ply Material:The type
of cord and number of plies in
the sidewall and under the tread.
(2) Temporary Use Only
:The
compact spare tire or temporary
use tire should not be driven at
speeds over 80 km/h (50 mph).
The compact spare tire is for
emergency use when a regular road tire has lost air and gone
flat. If the vehicle has a compact
spare tire, see
Compact Spare
Tire 0292 andIf a Tire Goes
Flat 0279.
(3) Tire Identification Number
(TIN)
:The letters and numbers
following the DOT (Department
of Transportation) code are the
Tire Identification Number (TIN).
The TIN shows the
manufacturer and plant code,
tire size, and date the tire was
manufactured. The TIN is
molded onto both sides of the
tire, although only one side may
have the date of manufacture.
(4) Maximum Cold Inflation
Load Limit
:Maximum load that
can be carried and the
maximum pressure needed to
support that load.
(5) Tire Inflation
:The
temporary use tire or compact
spare tire should be inflated to
420 kPa (60 psi). For more

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
Vehicle Care 263
information on tire pressure and
inflation seeTire Pressure
0 266.
(6) Tire Size
:A combination of
letters and numbers define a
tire's width, height, aspect ratio,
construction type, and service
description. The letter T as the
first character in the tire size
means the tire is for temporary
use only.
(7) TPC Spec (Tire
Performance Criteria
Specification)
:Original
equipment tires designed to
GM's specific tire performance
criteria have a TPC specification
code molded onto the sidewall.
GM's TPC specifications meet or
exceed all federal safety
guidelines.
Tire Designations
Tire Size
The following is an example of a
typical passenger vehicle
tire size.
(1) Passenger (P-Metric) Tire:
The United States version of a
metric tire sizing system. The
letter P as the first character in
the tire size means a passenger
vehicle tire engineered to
standards set by the U.S. Tire
and Rim Association.
(2) Tire Width
:The three-digit
number indicates the tire section
width in millimeters from
sidewall to sidewall. (3) Aspect Ratio
:A two-digit
number that indicates the tire
height-to-width measurements.
For example, if the tire size
aspect ratio is 60, as shown in
item 3 of the illustration, it would
mean that the tire's sidewall is
60 percent as high as it is wide.
(4) Construction Code
:A letter
code is used to indicate the type
of ply construction in the tire.
The letter R means radial ply
construction; the letter D means
diagonal or bias ply
construction; and the letter B
means belted-bias ply
construction.
(5) Rim Diameter
:Diameter of
the wheel in inches.
(6) Service Description
:These
characters represent the load
index and speed rating of the
tire. The load index represents
the load carrying capacity a tire
is certified to carry. The speed
rating is the maximum speed a
tire is certified to carry a load.