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264 Vehicle Care
FusesUsage
56 –
57 Transmission auxiliary pump
58 Transmission range control module
59 High-beam headlamps
60 Cooling fan
61 –
62 –
63 –
65 Air conditioning (HEV)
67 –
68 –
69 Right HID low-beam headlamps
70 Left HID low-beam headlamps
72 Starter pinion
74 Starter motor Fuses
Usage
75 Engine control module
76 Powertrain –off
engine
77 –
78 Horn
79 Washer pump
81 Transmission control module/Engine
control module
82 –
83 Ignition coil –odd
84 Ignition coil –even
85 Shunt
86 Shunt
87 –
88 Aeroshutter
89 Headlamp washer
91 – Fuses
Usage
92 Traction power inverter module/
Motor generator unit
coolant motor
93 Headlamp leveling
95 –
96 –
97 –
99 Coolant pump
Relays Usage
4 –
20 Rear defogger
25 Front wiper control
31 Run/Crank
37 Front wiper speed
42 Transmission auxiliary pump
64 Air conditioning control
66 Powertrain
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Vehicle Care 265
RelaysUsage
71 HID low-beam headlamps
73 Starter motor
80 Starter pinion
90 –
94 Headlamp washer
98 –
Instrument 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.
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266 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 – Fuses
Usage
F4 Heating ventilation & air conditioning
blower motor
F5 Body control module 2
F6 Electric steering column
F7 – Fuses
Usage
F8 Body control module 3
F9 Engine control module/Battery
F10 Body control module 2 (stop/start)
F11 –
F12 –
F13 –
F14 –
F15 Transmission control module (stop/start)
F16 Amplifier
F17 –
F18 Body control module 7
F19 –
F20 Body control module 1
F21 Body control module 4
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Vehicle Care 267
FusesUsage
F22 Body control module 6
F23 Electric steering column lock
F24 Airbag sensing diagnostic module/
Passenger sensing
module
F25 Data link connector
F26 –
F27 AC DC inverter
F28 HID headlamps
F29 Body control module 8
F30 Overhead console
F31 Steering wheel control
F32 –
F33 Heating, ventilation & air conditioning
F34 Communication gateway module Fuses
Usage
F35 Integrated chassis control module
F36 Charger
F37 Auxiliary power outlet/Cigar lighter
F38 OnStar
F39 Display
F40 Obstacle detection
F41 Body control module 1 (stop/start)
F42 Radio
F43 Rear accessory power outlet
F44 Front accessory power outlet
Relays Usage
K1 –
K2 Retained accessory power
K3 –
K4 – Relays
Usage
K5 Logistics
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Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
2019 - crc - 8/20/18
268 Vehicle Care
Wheels 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. SeeVehicle Load
Limits 0172.
(Continued)
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
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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 0269.
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
for details regarding winter tire
availability and proper tire selection.
Also, see
Buying New Tires 0282.
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.
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270 Vehicle Care
(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 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 0284.
(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
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Vehicle Care 271
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, seeCompact Spare
Tire 0300 andIf a Tire Goes
Flat 0287.
(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
information on tire pressure and
inflation see Tire Pressure
0 275.
(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.