Page 180 of 512

Black plate (8,1)Buick LaCrosse Owner Manual - 2012
6-8 Lighting
The battery can be discharged at
idle if the electrical loads are very
high. This is true for all vehicles.
This is because the generator
(alternator) may not be spinning fast
enough at idle to produce all of the
power needed for very high
electrical loads.
A high electrical load occurs when
several of the following are on, such
as: headlamps, high beams, fog
lamps, rear window defogger,
climate control fan at high speed,
heated seats, engine cooling fans,
trailer loads, and loads plugged into
accessory power outlets.EPM works to prevent excessive
discharge of the battery. It does this
by balancing the generator's output
and the vehicle's electrical needs.
It can increase engine idle speed to
generate more power whenever
needed. It can temporarily reduce
the power demands of some
accessories.
Normally, these actions occur in
steps or levels, without being
noticeable. In rare cases at the
highest levels of corrective action,
this action may be noticeable to the
driver. If so, a DIC message might
be displayed and it is recommended
that the driver reduce the electrical
loads as much as possible. See
Battery Voltage and Charging
Messages on page 5‑35.Battery Power Protection
The battery saver feature is
designed to protect the vehicle's
battery.
If the exterior lamps or any interior
light is left on and the ignition is
turned off, the battery rundown
protection system automatically
turns the lamp off after about
10 minutes.
Page 368 of 512

Black plate (30,1)Buick LaCrosse Owner Manual - 2012
10-30 Vehicle Care
Headlamp Aiming
The headlamp aiming system has
been preset at the factory.
If the vehicle is damaged in an
accident, the aim of the headlamps
may be affected and adjustment
may be necessary.
It is recommended that a dealer
adjust the headlamps. To re-aim the
headlamps yourself, use the
following procedure.
The vehicle should be properly
prepared as follows:
.The vehicle should be placed so
the headlamps are 7.6 m (25 ft)
from a light‐colored wall.
.The vehicle must have all four
tires on a level surface which is
level all the way to the wall.
.The vehicle should be placed so
it is perpendicular to the wall or
other flat surface.
.The vehicle should not have any
snow, ice, or mud on it.
.The vehicle should be fully
assembled and all other work
stopped while headlamp aiming
is being performed.
.The vehicle should be normally
loaded with a full tank of fuel and
one person or 75 kg (160 lbs)
sitting in the driver seat.
.Tires should be properly inflated.
Headlamp aiming is done with the
vehicle's low-beam headlamps. The
high-beam headlamps will be
correctly aimed if the low-beam
headlamps are aimed properly. To adjust the vertical aim:
1. Open the hood. See
Hood on
page 10‑5.
Base
Page 369 of 512
Black plate (31,1)Buick LaCrosse Owner Manual - 2012
Vehicle Care 10-31
Uplevel
2. Locate the aim dot on the lens of the low‐beam headlamp.
3. Measure the distance from the ground to the aim dot on the
low‐beam headlamp. Record the
distance.
4. At the wall, measure from theground upward (A) to the
recorded distance from
Step 3 and mark it.
5. Draw or tape a horizontal line (B) on the wall the width of the
vehicle at the height of the mark
in Step 4. Notice:
Do not cover a headlamp
to improve beam cut-off when
aiming. Covering a headlamp may
cause excessive heat build-up
which may cause damage to the
headlamp.
6. Turn on the low-beam
headlamps and place a piece of
cardboard or equivalent in front
of the headlamp not being
adjusted. This allows only the
beam of light from the headlamp
being adjusted to be seen on the
flat surface.
Page 370 of 512
Black plate (32,1)Buick LaCrosse Owner Manual - 2012
10-32 Vehicle Care
Base
Uplevel7. Locate the vertical headlamp
aiming screws, which are under
the hood near each headlamp
assembly.
8. Turn the vertical aiming screw until the headlamp beam is
aimed to the horizontal tape line.
Turn it clockwise or
counterclockwise to raise or
lower the angle of the beam.
9. Make sure that the light from the
headlamp is positioned at the
bottom edge of the horizontal
tape line. The lamp on the
left (A) shows the correct
headlamp aim. The lamp on the
right (B) shows the incorrect
headlamp aim.
10. Repeat Steps 7 through 9 for the opposite headlamp.
Page 371 of 512

Black plate (33,1)Buick LaCrosse Owner Manual - 2012
Vehicle Care 10-33
Bulb Replacement
For the proper type of replacement
bulbs, seeReplacement Bulbs on
page 10‑36.
For any bulb changing procedure
not listed in this section, contact
your dealer.
Halogen Bulbs
{WARNING
Halogen bulbs have pressurized
gas inside and can burst if you
drop or scratch the bulb. You or
others could be injured. Be sure
to read and follow the instructions
on the bulb package.
High Intensity Discharge
(HID) Lighting
{WARNING
The low beam high intensity
discharge lighting system
operates at a very high voltage.
If you try to service any of the
system components, you could be
seriously injured. Have your
dealer or a qualified technician
service them.
After an HID headlamp bulb has
been replaced, the beam might be a
slightly different shade than it was
originally. This is normal.
Headlamps, Front Turn
Signal and Parking
Lamps
Base Headlamp Assembly
The base model vehicle has a
halogen high-beam headlamp, a
low-beam/Daytime Running Lamp
(DRL) headlamp, and a turn signal/
parking lamp on the headlamp
assembly.
For replacement of the turn signal/
parking lamp bulb on an eAssist
vehicle, contact your dealer.
Page 372 of 512

Black plate (34,1)Buick LaCrosse Owner Manual - 2012
10-34 Vehicle Care
To replace one of these bulbs:
1. Open the hood. SeeHood on
page 10‑5.
A. Low-Beam Headlamp/DRL
B. High-Beam Headlamp
C. Parking/Turn Signal Lamp
2. If replacing a headlamp bulb, remove the dust cover from the
back of the headlamp housing
by turning counterclockwise
one‐quarter turn. 3. If replacing a turn signal/parking
lamp bulb on a non‐eAssist
vehicle, remove the close out
panel push pins and close out
panel covering the bulb socket.
4. Remove the bulb socket from the headlamp by turning
counterclockwise
one‐quarter turn.
5. Remove the bulb from the socket. If replacing the
high/low‐beam bulb, pry the two
clips on either end of the bulb
and pull straight out.
6. Install the new bulb in the socket. 7. Install the bulb socket by turning
clockwise one‐quarter turn.
8. If a headlamp bulb was replaced, install the dust cover in
the back of the headlamp
housing by turning clockwise
one‐quarter turn.
Uplevel Headlamp Assembly
The uplevel model vehicle has a
high intensity discharge (HID) high/
low beam, a dedicated DRL, and a
parking/turn signal lamp on the
headlamp assembly. See High
Intensity Discharge (HID) Lighting
on page 10‑33 for more information.
Page 374 of 512

Black plate (36,1)Buick LaCrosse Owner Manual - 2012
10-36 Vehicle Care
License Plate Lamp
The license plate lamps for this
vehicle are on the trunk lid.
To replace one of these bulbs:
1. Open the trunk. SeeTrunk on
page 2‑13 for more information.
2. Push the end on either of the
lamp assemblies (passenger
side shown) and then move the
lamp assembly down to remove
it from the trunk lid.
A. Bulb Socket
B. Bulb
C. Lamp Assembly
3. Turn the bulb socket (A) counterclockwise to remove it
from the lamp assembly (C).
4. Pull the bulb (B) 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
Daytime Running
Lamp (Uplevel) 3157K LCP
Front Turn Signal/
Parking Lamp 3757NAK
LCP
Headlamp High
Beam (Base) H9
Headlamp Low
Beam (Base) H11LL
License Plate Lamp W5WLL
Rear Turn Signal 3757NAK
LCP
For replacement bulbs not listed
here, contact your dealer.
Page 379 of 512

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