Page 287 of 407

Black plate (34,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
10-34 Vehicle Care
3. Turn the bulb socket (1)counterclockwise to remove it
from the lamp assembly (3).
4. Pull the bulb (2) straight out of the bulb socket.
5. Push the replacement bulb straight into the bulb socket and
turn the bulb socket clockwise to
install it into the lamp assembly.
6. Move the lamp assembly into the trunk lid, engaging the clip
side first.
7. Push on the lamp side opposite the clip until the lamp assembly
snaps into place.
Replacement Bulbs
Exterior Lamp Bulb
Number
Back-Up Lamp 921LL (W16W)
Front Turn
Signal Lamp 7444NA
Headlamp High
Beam (Base) HIR2
Headlamp Low
Beam (Base) HIR2
License Plate Lamp W5WLL
Rear Turn Signal 7443NA (WY21W)
For replacement bulbs not listed
here, contact your dealer.
Electrical System
High Voltage Devices and
Wiring
{Warning
Exposure to high voltage can
cause shock, burns, and even
death. The high voltage
components in the vehicle can
only be serviced by technicians
with special training.
High voltage components are
identified by labels. Do not
remove, open, take apart,
or modify these components.
High voltage cable or wiring has
orange covering. Do not probe,
tamper with, cut, or modify high
voltage cable or wiring.
Page 292 of 407

Black plate (39,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Vehicle Care 10-39
Mini Fuses Usage52 Cluster Run/Crank
53 Run/Crank for Inside Rearview Mirror,
Rear Vision Camera,
Air Quality Sensor,
Aero Shutter Motor
54 Run/Crank for: Heating, Ventilation
and Air
Conditioning,
Headlamp Switch
55 Outside Rearview Mirror, Universal
Remote System,
Front Window
Switches
56 Windshield Washer
60 Heated Mirror
62 Canister Vent
64 Adaptive Forward Lighting (AFL)
Module–Battery
65 Not Used Mini Fuses Usage
66 AIR Solenoid (eAssist)
67 Fuel Pump Power Module/Chassis
Control Module
69 Regulated Voltage Control Sensor
70 Parking Assist/Side Blind Zone
71 Passive Entry/ Passive Start
Mini Relays Usage 7 Engine Control Module
9 Cooling Fan
13 Cooling Fan
15 Run/Crank
16 AIR Pump
17 Rear Window Defogger Micro
Relays Usage
1 Air Conditioning Compressor Clutch
2 Starter
4 Wiper Speed
5 Wiper Control
6 Cabin Heater Coolant Pump
(eAssist)/Secondary
Air Injector/
Secondary Air
Injector with
Pressure Sensor
10 Cooling Fan
14 Headlamp Low Beam
Ultra Micro Relays Usage
11 Transmission Auxiliary Oil Pump
(eAssist)
Page 399 of 407

Black plate (6,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
i-6 INDEX
Headlamps (cont'd)Flash-to-Pass . . . . . . . . . . . . . . . . . . 6-2
High Intensity Discharge
(HID) Lighting . . . . . . . . . . . . . 10-31
High-Beam On Light . . . . . . . . . . 5-25
High/Low Beam Changer . . . . . . 6-2
Lamps On Reminder . . . . . . . . . 5-25
Heated Steering Wheel . . . . . . . . . . . . . . . . 5-3
Heated and Ventilated Front Seats . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
Heated Mirrors . . . . . . . . . . . . . . . . . 2-19
Heater Engine . . . . . . . . . . . . . . . . . . . . . . . . 9-22
High Voltage Devices and Wiring . . . . . . . . . . . . . . . . . . . . . . . 10-34
High-Beam On Light . . . . . . . . . . . 5-25
High-Speed Operation . . . . . . . . 10-51
Hill and Mountain Roads . . . . . . . . 9-7
Hill Start Assist (HSA) . . . . . . . . . 9-33
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
How to Wear Safety Belts Properly . . . . . . . . . . . . . . . . . . . . . . 3-14I
Ignition Positions . . . . . . . . 9-15, 9-16
Ignition Transmission LockCheck . . . . . . . . . . . . . . . . . . . . . . . 10-29
Immobilizer . . . . . . . . . . . . . . . . . . . . 2-16
Indicator Vehicle Ahead . . . . . . . . . . . . . . . . 5-21
Infants and Young Children, Restraints . . . . . . . . . . . . . . . . . . . . 3-35
Information Energy . . . . . . . . . . . . . . . . . . . . . . . 5-27
Infotainment . . . . . . . . . . . . . . . . . . . . 7-1
Infotainment System . . . . . . . . . . 13-15
Instrument Cluster . . . . . . . . . . . . . . 5-8
Interior Rearview Mirrors . . . . . . . 2-19
Introduction . . . . . . . . . . . . . . . . . . . . . . . iii
J
Jump Starting . . . . . . . . . .10-78, 10-79
K
Key and Lock Messages . . . . . . . 5-39
Keyless Entry Remote (RKE) System . . . . . . . . 2-3
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
L
Labeling, Tire Sidewall . . . . . . . . 10-44
Lamps Daytime Running (DRL) . . . . . . . 6-2
Dome . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Exterior Controls . . . . . . . . . . . . . . . 6-1
Exterior Lamps OffReminder . . . . . . . . . . . . . . . . . . . . 6-2
Fog . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
Headlamps, Front Turn Signal, and Parking
Lamps . . . . . . . . . . . . . . . . . . . . 10-32
License Plate . . . . . . . . . . . . . . . 10-33
Malfunction Indicator . . . . . . . . . 5-16
Messages . . . . . . . . . . . . . . . . . . . . 5-40
Page 400 of 407

Black plate (7,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
INDEX i-7
Lamps (cont'd)On Reminder . . . . . . . . . . . . . . . . . 5-25
Reading . . . . . . . . . . . . . . . . . . . . . . . 6-6
Sun Visor . . . . . . . . . . . . . . . . . . . . . . 6-6
Lane Change Alert . . . . . . . . . . . . 9-55
Lane Departure Warning (LDW) . . . . . . . . . . . . . . . 9-57
Lane Departure Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . 5-21
Lap-Shoulder Belt . . . . . . . . . . . . . 3-15
LATCH System Replacing Parts after aCrash . . . . . . . . . . . . . . . . . . . . . . . 3-48
LATCH, Lower Anchors and
Tethers for Children . . . . . . . . . . 3-41
LED Lighting . . . . . . . . . . . . . . . . . . 10-31
Light Adaptive Forward Lighting
(AFL) Light . . . . . . . . . . . . . . . . . . 5-25
Lighting Adaptive Forward . . . . . . . . . . . . . . 6-3
Entry . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Exit . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Illumination Control . . . . . . . . . . . . 6-5
LED . . . . . . . . . . . . . . . . . . . . . . . . 10-31 Lights
Airbag Readiness . . . . . . . . . . . . . 5-14
Antilock Brake System
(ABS) Warning . . . . . . . . . . . . . . 5-20
Brake System Warning . . . . . . . 5-19
Charging System . . . . . . . . . . . . . 5-16
Cruise Control . . . . . . . . . . . . . . . . 5-25
Door Ajar . . . . . . . . . . . . . . . . . . . . . 5-26
Electric Parking Brake . . . . . . . . 5-20
Engine Coolant Temperature Warning . . . . . . . 5-22
Engine Oil Pressure . . . . . . . . . . 5-23
Flash-to-Pass . . . . . . . . . . . . . . . . . . 6-2
Front Fog Lamp . . . . . . . . . . . . . . 5-25
High-Beam On . . . . . . . . . . . . . . . . 5-25
High/Low Beam Changer . . . . . . 6-2
Lane Departure Warning . . . . . . 5-21
Low Fuel Warning . . . . . . . . . . . . 5-24
Safety Belt Reminders . . . . . . . . 5-14
Security . . . . . . . . . . . . . . . . . . . . . . 5-24
Service Electric Parking Brake . . . . . . . . . . . . . . . . . . . . . . . 5-20
StabiliTrak
®OFF . . . . . . . . . . . . . 5-22 Lights (cont'd)
Tire Pressure . . . . . . . . . . . . . . . . . 5-23
Traction Control System
(TCS)/StabiliTrak
®. . . . . . . . . . 5-22
Traction Off . . . . . . . . . . . . . . . . . . . 5-21
Limited-Slip Differential . . . . . . . . 9-36
Locks Automatic Door . . . . . . . . . . . . . . . 2-12
Delayed Locking . . . . . . . . . . . . . . 2-12
Door . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
Lockout Protection . . . . . . . . . . . . 2-12
Power Door . . . . . . . . . . . . . . . . . . . 2-11
Safety . . . . . . . . . . . . . . . . . . . . . . . . 2-12
Loss of Control . . . . . . . . . . . . . . . . . 9-6
Low Fuel Warning Light . . . . . . . . 5-24
Lower Anchors and Tethers
for Children (LATCH
System) . . . . . . . . . . . . . . . . . . . . . . 3-41
Lumbar Adjustment . . . . . . . . . . . . . 3-5 Front Seats . . . . . . . . . . . . . . . . . . . . 3-5