2012 BUICK LACROSSE relay

Black plate (28,1)Buick LaCrosse Owner Manual - 2012
1-28 In Brief
Roadside Service and OnStar
(U.S. and Canada)
If you have an active OnStar
subscription, press the
Qbutton
and the current GPS location will be
sent to an OnStar Advisor who will
assess your problem, contact
Roadside Assistance, and relay
your exact location to get the help
you need.
Online Owner Center (U.S. and
Canada)
The Online Owner Center is a
complimentary service that includes
online service reminders, vehicle
maintenance tips, online owner
manual, special privileges,
and more.
Sign up today at: U.S.: buick.com
(Click on "Owners," then
"Manage My Buick/Owners
Login")
Canada: buickowner.ca
OnStar®
If equipped, this vehicle has a
comprehensive, in-vehicle system
that can connect to a live Advisor
for Emergency, Security, Navigation,
Connection, and Diagnostic
Services. See OnStar Overview on
page 14‑1 for more information.

Black plate (38,1)Buick LaCrosse Owner Manual - 2012
10-38 Vehicle Care
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.
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 on
page 10‑38, Instrument Panel Fuse
Block on page 10‑42, and Rear
Compartment Fuse Block on
page 10‑44.
Engine Compartment
Fuse Block
To remove the fuse block cover,
squeeze the three retaining clips on
the cover and lift it straight up.
Notice: Spilling liquid on any
electrical component on the
vehicle may damage it. Always
keep the covers on any electrical
component.

Black plate (39,1)Buick LaCrosse Owner Manual - 2012
Vehicle Care 10-39
Engine Compartment Fuse Block
The vehicle may not be equipped
with all of the fuses, relays, and
features shown. J-CaseFuses Usage
6 Wiper
12 Starter J-Case
Fuses Usage
21 Rear Power
Windows
22 Sunroof
24 Front Power
Windows J-Case
Fuses Usage
25 Passive Entry/
Passive Start
Module
—Battery 2
(eAssist)
26 Antilock Brake
System Pump
27 Electric Park 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

Black plate (40,1)Buick LaCrosse Owner Manual - 2012
10-40 Vehicle Care
Mini Fuses Usage1 Transmission
Control
Module
—Battery
2 Engine Control
Module Battery
3 Air Conditioning
Compressor Clutch
5 Engine Control
Module Run/Crank
8 Ignition
Coils
—Even (Six
Cylinder Engine),
Ignition Coils —All
(Four Cylinder
Engine
9 Ignition Coils
—Odd
(Six Cylinder
Engine)
10 Engine Control
Module
—Switched
Battery (from Engine
Control Module
Relay) Mini Fuses Usage
11 Six Cylinder Engine:
Post Catalytic
Converter Oxygen
Sensor Heater,
Mass Air Flow
Sensor, Flex Fuel
Sensor
13 Run/Crank for
Transmission
Control Module and
Fuel System Control
Module
14 Cabin Heater
Coolant Pump
(eAssist)
15 Motor Generator
Unit Coolant Pump
(eAssist)
16 Run/Crank for
eAssist Power
Inverter Module
17 Airbag
Module
—Run/
Crank Mini Fuses Usage
18 Vented Seats
(eAssist)
23 Variable Effort
Steering
(if equipped) or
eAssist Power
Inverter Module
29 Power Lumbar, Left
30 Power Lumbar,
Right or Power Pack
Cooling Fan
(eAssist)
31 Passive Entry/
Passive Start
Module
—Battery 1
(eAssist)
32 Body Control
Module 6
33 Heated
Seat
—Front
34 Antilock Brake
System Valves
35 Amplifier

Black plate (41,1)Buick LaCrosse Owner Manual - 2012
Vehicle Care 10-41
Mini Fuses Usage36 Adaptive Forward
Lighting (AFL)
Motors
—Battery
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, Mass Air
Flow Sensor.
48 Fog Lamps
49 Right High Intensity
Discharge
Headlamp Mini Fuses Usage
50 Left High Intensity
Discharge
Headlamp
51 Horn
52 Cluster Run/Crank
53 Run/Crank for Inside
Rearview Mirror,
Rear Vision Camera
54 Run/Crank for:
Heating, Ventilation
and Air Conditioning
55 Outside Rearview
Mirror, Universal
Garage Door
Opener, Front
Window Switches
56 Windshield Washer
60 Heated Mirror
62 Canister Vent
64 Adaptive Forward
Lighting (AFL)
Module
—Battery Mini Fuses Usage
65 Not Used
66 AIR Solenoid
(eAssist)
67 Fuel System Control
Module
69 Regulated Voltage
Control Sensor
70 Ultrasonic Parking
Assist/Side
Blind Zone
Mini Relays Usage 7 Engine Control
Module
9 Cooling Fan
13 Cooling Fan
15 Run/Crank
16 AIR Pump
17 Rear Window
Defogger

Black plate (42,1)Buick LaCrosse Owner Manual - 2012
10-42 Vehicle Care
Micro
Relays Usage
1 Air Conditioning
Compressor Clutch
2 Starter
4 Wiper Speed
5 Wiper Control
6 Cabin Heater
Coolant Pump
(eAssist)
10 Cooling Fan
14 Headlamp
Low Beam
Ultra Micro Relays Usage
11 Transmission
Auxiliary Oil Pump
(eAssist)Instrument Panel Fuse
Block
The instrument panel fuse block is
located in the instrument panel, on
the driver side of the vehicle. To
access the fuses, open the fuse
panel door by pulling down at
the top.
Press in on the sides of the door to
release it from the instrument panel.
Pull the door toward you to release
it from the hinge.

Black plate (43,1)Buick LaCrosse Owner Manual - 2012
Vehicle Care 10-43
Instrument Panel Fuse Block
The vehicle may not be equipped
with all of the fuses, relays, and
features shown. Fuses Usage
1 Steering Wheel
Controls Backlight
2 Body Control
Module 7
3 Body Control
Module 5
4 Radio
5 OnStar
6 Power Outlet 1
7 Power Outlet 2
8 Body Control
Module 1
9 Body Control
Module 4
10 Body Control
Module 8
(J‐Case Fuse) Fuses Usage
11 Front Heater
Ventilation Air
Conditioning/Blower
(J‐Case Fuse)
12 Passenger Seat
(Circuit Breaker)
13 Driver Seat (Circuit
Breaker)
14 Diagnostic Link
Connector
15 Airbag
16 Trunk
17 Heater Ventilation
Air Conditioning
Controller
18 Pre‐Fuse for Fuses
4 and 5

Black plate (44,1)Buick LaCrosse Owner Manual - 2012
10-44 Vehicle Care
FusesUsage
19 Infotainment and
Center Stack
Displays, Head‐Up
Display, Preferred
Device Interface
Module, Rear Seat
Infotainment
(eAssist)
20 Automatic Occupant
Sensing
21 Instrument Panel
Cluster
22 Discrete Logic
Ignition Switch Fuses
Usage
23 Body Control
Module 3
24 Body Control
Module 2
25 Rear Heater
Ventilation Air
Conditioning/Blower
26 AC/DC Inverter
Relays Usage
R1 Trunk Relay
R2 Not Used
R3 Power Outlet RelayRear Compartment Fuse
Block
The rear compartment fuse block is
located on the left side of the trunk
behind a cover. Vehicles with
eAssist do not have a rear
compartment fuse block.