check engine BUICK LACROSSE 2012 User Guide

Black plate (22,1)Buick LaCrosse Owner Manual - 2012
9-22 Driving and Operating
Starting the Engine
Move the shift lever to P (Park) or
N (Neutral). The engine will not start
in any other position. To restart the
engine when the vehicle is already
moving, use N (Neutral) only.
Notice:Do not try to shift to
P (Park) if the vehicle is moving.
If you do, you could damage the
transmission. Shift to P (Park)
only when the vehicle is stopped.
Notice: The engine is designed to
work with the electronics in the
vehicle. If you add electrical parts
or accessories, you could change
the way the engine operates.
Before adding electrical
equipment, check with your
dealer. If you do not, the engine
might not perform properly. Any
resulting damage would not be
covered by the vehicle warranty. Starting Procedure (Key Access)
1. With your foot off the accelerator
pedal, turn the ignition key to
START. When the engine starts,
let go of the ignition.
The idle speed will go down as
your engine gets warm. Do not
race the engine immediately
after starting it. Operate the
engine and transmission gently
to allow the oil to warm up and
lubricate all moving parts.
The vehicle has a
Computer-Controlled Cranking
System. This feature assists in
starting the engine and protects
components. If the ignition key is
turned to the START position,
and then released when the
engine begins cranking, the
engine will continue cranking for
a few seconds or until the
vehicle starts. If the engine does
not start and the key is held in
START for many seconds,
cranking will be stopped after
15 seconds to prevent cranking motor damage. To prevent gear
damage, this system also
prevents cranking if the engine
is already running. Engine
cranking can be stopped by
turning the ignition switch to
ACC/ACCESSORY or
LOCK/OFF.
Notice: Cranking the engine for
long periods of time, by returning
the key to the START position
immediately after cranking has
ended, can overheat and damage
the cranking motor, and drain the
battery. Wait at least 15 seconds
between each try, to let the
cranking motor cool down.
2. If the engine does not start after five to 10 seconds, especially in
very cold weather (below −18°C
or 0°F), it could be flooded with
too much gasoline. Try pushing
the accelerator pedal all the way
to the floor and holding it there
as you hold the key in START,
or press the START button, for
up to a maximum of 15 seconds.
Wait at least 15 seconds

Black plate (35,1)Buick LaCrosse Owner Manual - 2012
Driving and Operating 9-35
Brakes
Antilock Brake
System (ABS)
This vehicle has the Antilock Brake
System (ABS), an advanced
electronic braking system that helps
prevent a braking skid.
When the engine is started and the
vehicle begins to drive away, ABS
checks itself. A momentary motor or
clicking noise might be heard while
this test is going on, and it might
even be noticed that the brake
pedal moves a little. This is normal.
If there is a problem with ABS, this
warning light stays on. SeeAntilock
Brake System (ABS) Warning Light
on page 5‑21. If driving safely on a wet road and it
becomes necessary to slam on the
brakes and continue braking to
avoid a sudden obstacle, a
computer senses that the wheels
are slowing down. If one of the
wheels is about to stop rolling, the
computer will separately work the
brakes at each wheel.
ABS can change the brake pressure
to each wheel, as required, faster
than any driver could. This can help
the driver steer around the obstacle
while braking hard.
As the brakes are applied, the
computer keeps receiving updates
on wheel speed and controls
braking pressure accordingly.
Remember: ABS does not change
the time needed to get a foot up to
the brake pedal or always decrease
stopping distance. If you get too
close to the vehicle in front of you,
there will not be enough time to
apply the brakes if that vehicle
suddenly slows or stops. Always
leave enough room up ahead to
stop, even with ABS.
Using ABS
Do not pump the brakes. Just hold
the brake pedal down firmly and let
ABS work. You might hear the ABS
pump or motor operating and feel
the brake pedal pulsate, but this is
normal.
Braking in Emergencies
ABS allows the driver to steer and
brake at the same time. In many
emergencies, steering can help
more than even the very best
braking.

Black plate (36,1)Buick LaCrosse Owner Manual - 2012
9-36 Driving and Operating
Parking Brake
The vehicle has an Electric Parking
Brake (EPB). The switch for the
EPB is in the center console. The
EPB can always be activated, even
if the ignition is off. To prevent
draining the battery, avoid repeated
cycles of the EPB system when the
engine is not running.
The system has a parking brake
status light and a parking brake
warning light. SeeElectric Parking
Brake Light on page 5‑21. There are
also three Driver Information Center (DIC) messages. See
Brake System
Messages on page 5‑36 for more
information. In case of insufficient
electrical power, the EPB cannot be
applied or released.
Before leaving the vehicle, check
the parking brake status light to
ensure that the parking brake is
applied.
EPB Apply
The EPB can be applied any time
the vehicle is stopped. The EPB is
applied by momentarily lifting up on
the EPB switch. Once fully applied,
the parking brake status light will be
on. While the brake is being applied,
the status light will flash until full
apply is reached. If the light does
not come on, or remains flashing,
have the vehicle serviced. Do not
drive the vehicle if the parking brake
status light is flashing. See your
dealer. See Electric Parking Brake
Light on page 5‑21 for more
information. If the EPB is applied while the
vehicle is in motion, a chime will
sound, and a DIC message will be
displayed. See
Brake System
Messages on page 5‑36. The
vehicle will decelerate as long as
the switch is held in the up position.
Releasing the EPB switch during
deceleration will release the parking
brake. If the switch is held in the up
position until the vehicle comes to a
stop, the EPB will remain applied.
If the parking brake status light
flashes continuously, the EPB is
only partially applied or released,
or there is a problem with the EPB.
A DIC message will be displayed.
See Brake System Messages on
page 5‑36. If this light flashes
continuously, release the EPB, and
attempt to apply it again. If this light
continues to flash, do not drive the
vehicle. See your dealer.

Black plate (52,1)Buick LaCrosse Owner Manual - 2012
9-52 Driving and Operating
When the System Does Not
Seem to Work Properly
The RVC system may not work
properly or display a clear image if:
.The RVC is turned off. See
“Turning the Rear Camera
System On or Off”earlier in this
section.
.It is dark.
.The sun or the beam of
headlamps are shining directly
into the camera lens.
.Ice, snow, mud, or anything else
builds up on the camera lens.
Clean the lens, rinse it with
water, and wipe it with a soft
cloth.
.The back of the vehicle is in an
accident. The position and
mounting angle of the camera
can change or the camera can
be affected. Be sure to have the
camera and its position and
mounting angle checked at your
dealer.
Fuel
Use of the recommended fuel is an
important part of the proper
maintenance of this vehicle. To help
keep the engine clean and maintain
optimum vehicle performance, we
recommend the use of gasoline
advertised as TOP TIER Detergent
Gasoline.
Look for the TOP TIER label on the
fuel pump to ensure gasoline meets
enhanced detergency standards
developed by auto companies. A list
of marketers providing TOP TIER
Detergent Gasoline can be found at
www.toptiergas.com.
The eighth digit of the Vehicle
Identification Number (VIN) shows
the code letter or number that
identifies the vehicle's engine. The
VIN is at the top left of the
instrument panel. See Vehicle
Identification Number (VIN) on
page 12‑1.

Black plate (53,1)Buick LaCrosse Owner Manual - 2012
Driving and Operating 9-53
Recommended Fuel
Use regular unleaded gasoline with
a posted octane rating of 87 or
higher. If the octane rating is less
than 87, an audible knocking noise,
commonly referred to as spark
knock, might be heard when driving.
If this occurs, use a gasoline rated
at 87 octane or higher as soon as
possible. If heavy knocking is heard
when using gasoline rated at
87 octane or higher, the engine
needs service.
Gasoline Specifications
(U.S. and Canada Only)
At a minimum, gasoline should meet
ASTM specification D 4814
in the United States or CAN/
CGSB‐3.5 or 3.511 in Canada.
Some gasolines contain an
octane-enhancing additive called
methylcyclopentadienyl manganese
tricarbonyl (MMT). We recommend
against the use of gasolinescontaining MMT. See
Fuel Additives
on page 9‑53 for additional
information.
California Fuel
Requirements
If the vehicle is certified to meet
California Emissions Standards, it is
designed to operate on fuels that
meet California specifications. See
the underhood emission control
label. If this fuel is not available in
states adopting California Emissions
Standards, the vehicle will operate
satisfactorily on fuels meeting
federal specifications, but emission
control system performance might
be affected. The malfunction
indicator lamp could turn on and the
vehicle might fail a smog‐check test.
See Malfunction Indicator Lamp on
page 5‑17. If this occurs, return to
your authorized dealer for diagnosis.
If it is determined that the condition
is caused by the type of fuel used,
repairs might not be covered by the
vehicle warranty.
Fuels in Foreign
Countries
Never use leaded gasoline or any
other fuel not recommended in the
previous text on fuel. Costly repairs
caused by use of improper fuel
would not be covered by the vehicle
warranty.
To check the fuel availability, ask an
auto club, or contact a major oil
company that does business in the
country where you will be driving.
Fuel Additives
To provide cleaner air, all gasolines
in the United States are now
required to contain additives that
help prevent engine and fuel system
deposits from forming, allowing the
emission control system to work
properly. In most cases, nothing
should have to be added to the fuel.

Black plate (58,1)Buick LaCrosse Owner Manual - 2012
9-58 Driving and Operating
Pulling a Trailer
Here are some important points:
.There are many laws, including
speed limit restrictions that apply
to trailering. Check for legal
requirements.
.Do not tow a trailer at all during
the first 1 600 km (1,000 mi) the
new vehicle is driven. The
engine, axle, or other parts could
be damaged.
.During the first 800 km (500 mi)
that a trailer is towed, do not
drive over 80 km/h (50 mph) and
do not make starts at full throttle.
This reduces wear on the
vehicle.
.The vehicle can tow in D (Drive).
Use a lower gear if the
transmission shifts too often.
.Obey speed limit restrictions. Do
not drive faster than the
maximum posted speed for
trailers, or no more than 90 km/h
(55 mph), to reduce wear on the
vehicle.
Driving with a Trailer
Towing a trailer requires experience.
Get familiar with handling and
braking with the added trailer
weight. The vehicle is now longer
and not as responsive as the
vehicle is by itself.
Check all trailer hitch parts and
attachments, safety chains,
electrical connectors, lamps, tires,
and mirror adjustments. If the trailer
has electric brakes, start the vehicle
and trailer moving and then apply
the trailer brake controller by hand
to be sure the brakes are working.
During the trip, check regularly to be
sure that the load is secure, and the
lamps and trailer brakes are working
properly.
Towing with a Stability Control
System
When towing, the sound of the
stability control system might be
heard. The system is reacting to the
vehicle movement caused by the
trailer, which mainly occurs during
cornering. This is normal when
towing heavier trailers.
Following Distance
Stay at least twice as far behind the
vehicle ahead as you would when
driving the vehicle without a trailer.
This can help to avoid situations
that require heavy braking and
sudden turns.
Passing
More passing distance is needed
when towing a trailer. Because the
rig is longer, it is necessary to go
farther beyond the passed vehicle
before returning to the lane.

Black plate (59,1)Buick LaCrosse Owner Manual - 2012
Driving and Operating 9-59
Backing Up
Hold the bottom of the steering
wheel with one hand. To move the
trailer to the left, move that hand to
the left. To move the trailer to the
right, move your hand to the right.
Always back up slowly and,
if possible, have someone
guide you.
Making Turns
Notice:Making very sharp turns
while trailering could cause the
trailer to come in contact with the
vehicle. The vehicle could be
damaged. Avoid making very
sharp turns while trailering.
When turning with a trailer, make
wider turns than normal so the
trailer will not strike soft shoulders,
curbs, road signs, trees, or other
objects. Use the turn signal well in
advance and avoid jerky or sudden
maneuvers.
Turn Signals when Towing a
Trailer
The turn signal indicators on the
instrument panel flash whenever
signaling a turn or lane change.
Properly hooked up, the trailer
lamps also flash, telling other
drivers the vehicle is turning,
changing lanes, or stopping.
When towing a trailer, the arrows on
the instrument panel flash for turns
even if the bulbs on the trailer are
burned out. Check occasionally to
be sure the trailer bulbs are still
working.
Driving on Grades
Reduce speed and shift to a lower
gear before starting down a long or
steep downgrade. If the
transmission is not shifted down, the
brakes might have to be used so
much that they would get hot and no
longer work well. The vehicle can tow in D (Drive).
Use a lower gear if the transmission
shifts too often.
When towing at high altitude on
steep uphill grades, engine coolant
boils at a lower temperature than at
normal altitudes. If the engine is
turned off immediately after towing
at high altitude on steep uphill
grades, the vehicle could show
signs similar to engine overheating.
To avoid this, let the engine run
while parked, preferably on level
ground, with the transmission in
P (Park) for a few minutes before
turning the engine off. If the
overheat warning comes on, see
Engine Overheating on page 10‑19.

Black plate (60,1)Buick LaCrosse Owner Manual - 2012
9-60 Driving and Operating
Parking on Hills
{WARNING
Parking the vehicle on a hill with
the trailer attached can be
dangerous. If something goes
wrong, the rig could start to move.
People can be injured, and both
the vehicle and the trailer can be
damaged. When possible, always
park the rig on a flat surface.
If parking the rig on a hill:
1. Press the brake pedal, but do not shift into P (Park) yet. Turn
the wheels into the curb if facing
downhill or into traffic if facing
uphill.
2. Have someone place chocks under the trailer wheels. 3. When the wheel chocks are in
place, release the brake pedal
until the chocks absorb the load.
4. Reapply the brake pedal. Then apply the parking brake and shift
into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal while you:
1.1. Start the engine.
1.2. Shift into a gear.
1.3. Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance when Trailer
Towing
The vehicle needs service more
often when pulling a trailer. See the
Maintenance Schedule on
page 11‑3. Things that are
especially important in trailer
operation are automatic
transmission fluid, engine oil, axle
lubricant, belts, cooling system, and
brake system. Inspect these before
and during the trip.
Check periodically to see that all
hitch nuts and bolts are tight.
Engine Cooling when Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. See Engine Overheating
on page 10‑19.

Black plate (1,1)Buick LaCrosse Owner Manual - 2012
Vehicle Care 10-1
Vehicle Care
General Information
General Information . . . . . . . . . . 10-2
California Proposition65 Warning . . . . . . . . . . . . . . . . . 10-3
California Perchlorate Materials Requirements . . . . 10-3
Accessories and Modifications . . . . . . . . . . . . . . . 10-3
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 10-4
Hood . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . 10-6
Engine Oil . . . . . . . . . . . . . . . . . . . 10-9
Engine Oil Life System . . . . . 10-12
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . 10-13
Engine Air Cleaner/Filter . . . . 10-13
Cooling System . . . . . . . . . . . . 10-15
Engine Coolant . . . . . . . . . . . . . 10-16
Engine Overheating . . . . . . . . 10-19
Overheated Engine Protection
Operating Mode . . . . . . . . . . . 10-21 Power Steering Fluid (2.4L
L4 Engine) . . . . . . . . . . . . . . . . 10-21
Power Steering Fluid (3.6L V6 Engine) . . . . . . . . . . . . . . . . 10-21
Washer Fluid . . . . . . . . . . . . . . . 10-22
Brakes . . . . . . . . . . . . . . . . . . . . . 10-23
Brake Fluid . . . . . . . . . . . . . . . . . 10-24
Battery . . . . . . . . . . . . . . . . . . . . . 10-25
Starter Switch Check . . . . . . . 10-27
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . 10-27
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . 10-28
Park Brake and P (Park) Mechanism Check . . . . . . . . 10-28
Wiper Blade Replacement . . . . . . . . . . . . . . 10-29
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . 10-30
Bulb Replacement
Bulb Replacement . . . . . . . . . . 10-33
Halogen Bulbs . . . . . . . . . . . . . . 10-33
High Intensity Discharge(HID) Lighting . . . . . . . . . . . . . 10-33 Headlamps, Front Turn
Signal and Parking
Lamps . . . . . . . . . . . . . . . . . . . . 10-33
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . 10-35
License Plate Lamp . . . . . . . . 10-36
Replacement Bulbs . . . . . . . . . 10-36
Electrical System
High Voltage Devices and Wiring . . . . . . . . . . . . . . . . . . . . . 10-37
Electrical System Overload . . . . . . . . . . . . . . . . . . 10-37
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . 10-38
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . 10-38
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . 10-42
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . 10-44
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . 10-47
Winter Tires . . . . . . . . . . . . . . . . 10-48
Tire Sidewall Labeling . . . . . . 10-48
Tire Designations . . . . . . . . . . . 10-51

Black plate (9,1)Buick LaCrosse Owner Manual - 2012
Vehicle Care 10-9
A.Engine Air Cleaner/Filter on
page 10‑13.
B. Power Steering Reservoir and Cap. See Power Steering Fluid
(2.4L L4 Engine) on page 10‑21
or Power Steering Fluid (3.6L
V6 Engine) on page 10‑21.
C. Engine Oil Fill Cap. See Engine
Oil on page 10‑9.
D. Engine Oil Dipstick. See Engine
Oil on page 10‑9.
E. Engine Cover.
F. Transmission Fluid Cap and Dipstick. See Automatic
Transmission Fluid on
page 10‑13. G. Brake Master Cylinder
Reservoir. See Brakes on
page 10‑23.
H. Coolant Surge Tank and Pressure Cap. See Engine
Coolant on page 10‑16.
I. Battery Cover. See Battery on
page 10‑25.
J. Engine Compartment Fuse
Block on page 10‑38.
K. Windshield Washer Fluid Reservoir. See Washer Fluid on
page 10‑22.Engine Oil
To ensure proper engine
performance and long life, careful
attention must be paid to engine oil.
Following these simple, but
important steps will help protect
your investment:
.Always use engine oil approved
to the proper specification and of
the proper viscosity grade. See
“Selecting the Right Engine Oil”
in this section.
.Check the engine oil level
regularly and maintain the
proper oil level. See “Checking
Engine Oil” and“When to Add
Engine Oil” in this section.
.Change the engine oil at the
appropriate time. See Engine Oil
Life System on page 10‑12.
.Always dispose of engine oil
properly. See “What to Do with
Used Oil” in this section.