2012 BUICK LACROSSE cooling

Black plate (18,1)Buick LaCrosse Owner Manual - 2012
10-18 Vehicle Care
{WARNING
An electric engine cooling fan
under the hood can start up even
when the engine is not running
and can cause injury. Keep
hands, clothing, and tools away
from any underhood electric fan.
{WARNING
Steam and scalding liquids from a
hot cooling system can blow out
and burn you badly. They are
under pressure, and if you turn
the surge tank pressure
cap—even a little —they can
come out at high speed. Never
turn the cap when the cooling
system, including the surge tank
pressure cap, is hot. Wait for the
cooling system and surge tank
pressure cap to cool if you ever
have to turn the pressure cap.
The coolant surge tank pressure
cap can be removed when the
cooling system, including the surge
tank pressure cap and upper
radiator hose, is no longer hot.
1. Turn the pressure cap slowly counterclockwise. If a hiss is
heard, wait for that to stop.
A hiss means there is still some
pressure left.
2. Keep turning the cap and remove it.
3. Fill the coolant surge tank withthe proper mixture to the mark
pointed to on the front of the
coolant surge tank.

Black plate (19,1)Buick LaCrosse Owner Manual - 2012
Vehicle Care 10-19
4. With the coolant surge tank capoff, start the engine and let it run
until the upper radiator hose
starts getting hot. Watch out for
the engine cooling fans. By this
time, the coolant level inside the
coolant surge tank may be
lower. If the level is lower, add
more of the proper mixture to the
coolant surge tank until the level
reaches the mark pointed to on
the front of the coolant
surge tank.
5. Replace the cap. Be sure the cap is hand–tight and fully
seated.
Notice: If the pressure cap is not
tightly installed, coolant loss and
possible engine damage may
occur. Be sure the cap is properly
and tightly secured.Engine Overheating
2.4L L4 Engine
There is a engine coolant
temperature warning light on the
instrument panel cluster that
indicates an overheated engine
condition. See Engine Coolant
Temperature Warning Light on
page 5‑24 for more information.
3.6L V6 Engine
There is a coolant temperature
gauge and a engine coolant
temperature warning light on the
instrument panel cluster that
indicate an overheated engine
condition. See Engine Coolant
Temperature Gauge on page 5‑14
and Engine Coolant Temperature
Warning Light on page 5‑24 for
more information. If the decision is made not to lift the
hood when this warning appears,
get service help right away. See
Roadside Assistance Program
(U.S. and Canada) on page 13‑7
or
Roadside Assistance Program
(Mexico) on page 13‑10.
If the decision is made to lift the
hood, make sure the vehicle is
parked on a level surface.
Then check to see if the engine
cooling fans are running. If the
engine is overheating, the fans
should be running. If not, do not
continue to run the engine and have
the vehicle serviced.
Notice: Engine damage from
running the engine without
coolant is not covered by the
warranty.

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 (68,1)Buick LaCrosse Owner Manual - 2012
10-68 Vehicle Care
Replace wheels, wheel bolts, wheel
nuts, or Tire Pressure Monitor
System (TPMS) sensors with new
GM original equipment parts.
{WARNING
Using the wrong replacement
wheels, wheel bolts, or wheel
nuts can be dangerous. It could
affect the braking and handling of
the vehicle. Tires can lose air,
and cause loss of control, causing
a crash. Always use the correct
wheel, wheel bolts, and wheel
nuts for replacement.
Notice: The wrong wheel can
also cause problems with bearing
life, brake cooling, speedometer
or odometer calibration,
headlamp aim, bumper height,
vehicle ground clearance, and tire
or tire chain clearance to the
body and chassis.
See If a Tire Goes Flat on
page 10‑69 for more information.
Used Replacement Wheels
{WARNING
Replacing a wheel with a used
one is dangerous. How it has
been used or how far it has been
driven may be unknown. It could
fail suddenly and cause a crash.
When replacing wheels, use a
new GM original equipment
wheel.
Tire Chains
{WARNING
Do not use tire chains. There is
not enough clearance. Tire chains
used on a vehicle without the
proper amount of clearance can
cause damage to the brakes,
suspension, or other vehicle
parts. The area damaged by the
tire chains could cause loss of
control and a crash.
Use another type of traction
device only if its manufacturer
recommends it for the vehicle's
tire size combination and road
conditions. Follow that
manufacturer's instructions. To
avoid vehicle damage, drive slow
and readjust or remove the
traction device if it contacts the
vehicle. Do not spin the wheels.
If traction devices are used, install
them on the front tires.

Black plate (6,1)Buick LaCrosse Owner Manual - 2012
11-6 Service and Maintenance
Footnotes—Maintenance
Schedule Additional Required
Services —Normal
a) Or every two years, whichever
comes first. More frequent
replacement may be needed if the
vehicle is driven in areas with heavy
traffic, areas with poor air quality,
or areas with high dust levels.
Replacement may also be needed if
there is a reduction in air flow,
excessive window fogging, or odors. b)
Check all fuel and vapor lines
and hoses for proper hook‐up,
routing, and condition. Check that
the purge valve, if the vehicle has
one, works properly. Replace as
needed.
c) Or every four years, whichever
comes first.
d) Do not directly power wash the
transfer case output seals. High
pressure water can overcome the
seals and contaminate the transfer
case fluid. Contaminated fluid will
decrease the life of the transfer
case and should be replaced. e)
Or every five years, whichever
comes first. See Cooling System on
page 10‑15.
f) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage;
replace, if needed.