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Vehicle Care 259
After an HID headlamp bulb has
been replaced, the beam might be a
slightly different shade than it was
originally. This is normal.
LED Lighting
This vehicle has several LED lamps.
For replacement of any LED lighting
assembly, contact your dealer.
Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps
Driver Side Shown, PassengerSide Similar
1. Stoplamp/Turn Signal
2. Back-Up Lamp
To replace one of these bulbs:
1. Open the trunk. See Trunk
0 41.
2. Remove the fasteners to pull the trunk trim out. 3. Remove and retain the four
nuts fastening the taillamp
assembly to the vehicle body.
4. Remove the taillamp assembly by pulling straight back.
5. Remove the bulb socket by turning it counterclockwise.
6. Remove the old bulb by pulling it straight out.
7. Reverse Steps 1–6 to install.
License Plate Lamp
To replace one of these bulbs:
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Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
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260 Vehicle Care
1. Push the lamp assemblytoward the center of the
vehicle, then move the lamp
downward, and remove it from
the vehicle body.
2. Turn the bulb socket (1)
counterclockwise to remove it
from the lamp assembly (3).
3. Pull the bulb (2) out of the bulb socket.
4. Push the replacement bulb straight into the bulb socket
and turn the bulb socket
clockwise to install into the
lamp assembly. 5. Push the lamp assembly back
into position until the release
tab locks into place.
Electrical System
Electrical System
Overload
The vehicle has fuses and circuit
breakers to protect against an
electrical system overload.
When the current electrical load is
too heavy, the circuit breaker opens
and closes, protecting the circuit
until the current load returns to
normal or the problem is fixed. This
greatly reduces the chance of circuit
overload and fire caused by
electrical problems.
Fuses and circuit breakers protect
power devices in the vehicle.
Replace a bad fuse with a new one
of the identical size and rating.
If there is a problem on the road and
a fuse needs to be replaced, the
same amperage fuse can be
borrowed. Choose some feature of
the vehicle that is not needed to use
and replace it as soon as possible.
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Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
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Vehicle Care 261
Headlamp Wiring
An electrical overload may cause
the lamps to go on and off, or in
some cases to remain off. Have the
headlamp wiring checked right away
if the lamps go on and off or
remain off.
Windshield Wipers
If the wiper motor overheats due to
heavy snow or ice, the windshield
wipers will stop until the motor cools
and will then restart.
Although the circuit is protected
from electrical overload, overload
due to heavy snow or ice may
cause wiper linkage damage.
Always clear ice and heavy snow
from the windshield before using the
windshield wipers.
If the overload is caused by an
electrical problem and not snow or
ice, be sure to get it fixed.
Fuses and Circuit
Breakers
The wiring circuits in the vehicle are
protected from short circuits by a
combination of fuses and circuit
breakers. This greatly reduces the
chance of damage caused by
electrical problems.
{Danger
Fuses and circuit breakers are
marked with their ampere rating.
Do not exceed the
specified amperage rating when
replacing fuses and circuit
breakers. Use of an oversized
fuse or circuit breaker can result
in a vehicle fire. You and others
could be seriously injured or
killed.
To check a fuse, look at the
silver-colored band inside the fuse.
If the band is broken or melted,
replace the fuse. Be sure to replace
a bad fuse with a new one of the
identical size and rating. Fuses of the same amperage can
be temporarily borrowed from
another fuse location, if a fuse goes
out. Replace the fuse as soon as
possible.
To identify and check fuses, circuit
breakers, and relays, see
Engine
Compartment Fuse Block 0261 and
Instrument Panel Fuse Block 0265.
Engine Compartment
Fuse Block
To remove the fuse block cover,
squeeze the three retaining clips on
the cover and lift it straight up.
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Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
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262 Vehicle Care
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 –
2 –
3 Antilock brake system pump
5 – Fuses Usage
6 Rear closure
7 Left corner lamp
8 Power windows/ Rearview mirror/
Power seats
9 Electric brake boost/ Pedestrian alert
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Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
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Vehicle Care 263
FusesUsage
10 Airbag sensing diagnostic module/
Passenger sensing
module–eAssist
11 DC DC Battery 1
12 Rear window defogger
13 Heated mirrors
14 –
15 Passive entry/ Passive start
16 Front wipers
17 Passenger power seat
18 Antilock brake system valve
19 Driver power seat
21 Sunroof
22 Right corner lamp
23 Auto headlamp leveling
24 – Fuses
Usage
26 Transmission control module/Ignition
27 Instrument panel/ Ignition
28 –
29 Rear vision camera/ Ventilated seats
30 Malfunction indicator lamp/Shift solenoid
32 Canister vent solenoid
33 Front heated seats
34 Battery system manager/ Fan
control module/Rear
drive control module/
Damping control
module
35 Fog lamps
36 Fuel module
38 –
39 – Fuses
Usage
40 Steering columnn lock
41 –
43 Heated steering wheel
44 Headlamp leveling/ Rear seat ventilation
45 –
46 Engine control module/Ignition
47 –
48 Electric brake boost/ Left cooling fan
49 DC DC battery 2/ Rear drive control
module
50 –
51 –
52 –
53 –
54 –
55 –
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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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Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-12032549) -
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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) -
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284 Vehicle Care
Warning (Continued)
suddenly and cause a crash.
Use only radial-ply tires with
the wheels on the vehicle.
If the vehicle tires must be
replaced with a tire that does not
have a TPC Spec number, make
sure they are the same size,
load range, speed rating, and
construction (radial) as the
original tires.
Vehicles that have a tire
pressure monitoring system
could give an inaccurate
low-pressure warning if non-TPC
Spec rated tires are installed.
See Tire Pressure Monitor
System 0276.
The Tire and Loading
Information label indicates the
original equipment tires on the
vehicle. See Vehicle Load Limits
0 172.Different Size Tires and
Wheels
If wheels or tires are installed that
are a different size than the original
equipment wheels and tires, vehicle
performance, including its braking,
ride and handling characteristics,
stability, and resistance to rollover
may be affected. If the vehicle has
electronic systems such as antilock
brakes, rollover airbags, traction
control, electronic stability control,
or All-Wheel Drive, the performance
of these systems can also be
affected.
{Warning
If different sized wheels are used,
there may not be an acceptable
level of performance and safety if
tires not recommended for those
wheels are selected. This
increases the chance of a crash
and serious injury. Only use GM
specific wheel and tire systems
(Continued)
Warning (Continued)
developed for the vehicle, and
have them properly installed by a
GM certified technician.
See Buying New Tires 0282 and
Accessories and Modifications
0 236.
Uniform Tire Quality
Grading
The following information relates
to the system developed by the
United States National Highway
Traffic Safety Administration
(NHTSA), which grades tires by
treadwear, traction, and
temperature performance. This
applies only to vehicles sold in
the United States. The grades
are molded on the sidewalls of
most passenger car tires. The
Uniform Tire Quality Grading
(UTQG) system does not apply
to deep tread, winter tires,