
Black plate (18,1)Buick LaCrosse Owner Manual - 2012
5-18 Instruments and Controls
If the malfunction indicator lamp
comes on and stays on while the
engine is running, this indicates that
there is an OBD II problem and
service is required.
Malfunctions often are indicated by
the system before any problem is
apparent. Being aware of the light
can prevent more serious damage
to the vehicle. This system assists
the dealer technician in correctly
diagnosing any malfunction.
Notice:If the vehicle is
continually driven with this light
on, the emission controls might
not work as well, the vehicle fuel
economy might not be as good,
and the engine might not run as
smoothly. This could lead to
costly repairs that might not be
covered by the vehicle warranty. Notice:
Modifications made to the
engine, transmission, exhaust,
intake, or fuel system of the
vehicle or the replacement of the
original tires with other than
those of the same Tire
Performance Criteria (TPC) can
affect the vehicle's emission
controls and can cause this light
to come on. Modifications to
these systems could lead to
costly repairs not covered by the
vehicle warranty. This could also
result in a failure to pass a
required Emission Inspection/
Maintenance test. See
Accessories and Modifications on
page 10‑3.
This light comes on during a
malfunction in one of two ways:
Light Flashing: A misfire condition
has been detected. A misfire
increases vehicle emissions and
could damage the emission control
system on the vehicle. Diagnosis
and service might be required. To prevent more serious damage to
the vehicle:
.Reduce vehicle speed.
.Avoid hard accelerations.
.Avoid steep uphill grades.
.If the vehicle is towing a trailer,
reduce the amount of cargo
being hauled as soon as it is
possible.
If the light continues to flash, when
it is safe to do so, stop the vehicle.
Find a safe place to park. Turn the
vehicle off, wait at least 10 seconds,
and restart the engine. If the light is
still flashing, follow the previous
steps and see your dealer for
service as soon as possible.
Light On Steady: An emission
control system malfunction has
been detected on the vehicle.
Diagnosis and service might be
required.

Black plate (19,1)Buick LaCrosse Owner Manual - 2012
Instruments and Controls 5-19
The following may correct an
emissions system malfunction:
.Check that the fuel cap is fully
installed. SeeFilling the Tank on
page 9‑55. The diagnostic
system can determine if the fuel
cap has been left off or
improperly installed. A loose or
missing fuel cap allows fuel to
evaporate into the atmosphere.
A few driving trips with the cap
properly installed should turn the
light off.
.Check that good quality fuel is
used. Poor fuel quality causes
the engine not to run as
efficiently as designed and may
cause stalling after start-up,
stalling when the vehicle is
changed into gear, misfiring,
hesitation on acceleration,
or stumbling on acceleration.
These conditions might go away
once the engine is warmed up. If one or more of these conditions
occurs, change the fuel brand used.
It will require at least one full tank of
the proper fuel to turn the light off.
See
Recommended Fuel on
page 9‑53.
If none of the above have made the
light turn off, your dealer can check
the vehicle. The dealer has the
proper test equipment and
diagnostic tools to fix any
mechanical or electrical problems
that might have developed.Emissions Inspection and
Maintenance Programs
Some local governments may have
programs to inspect the on-vehicle
emission control equipment. For the
inspection, the emission system test
equipment is connected to the
vehicle’s Data Link
Connector (DLC).
The DLC is under the instrument
panel next to the steering wheel.
See your dealer if assistance is
needed.
The vehicle may not pass
inspection if:
.The malfunction indicator lamp is
on while the vehicle is running.
The vehicle is in ON/RUN for
keyed access, or service only
mode for keyless access and the
malfunction indicator lamp does
not come on. See your dealer for
assistance in verifying proper
operation of the malfunction
indicator lamp.

Black plate (25,1)Buick LaCrosse Owner Manual - 2012
Instruments and Controls 5-25
Engine Oil Pressure Light
{WARNING
Do not keep driving if the oil
pressure is low. The engine can
become so hot that it catches fire.
Someone could be burned. Check
the oil as soon as possible and
have the vehicle serviced.
Notice: Lack of proper engine oil
maintenance can damage the
engine. The repairs would not be
covered by the vehicle warranty.
Always follow the maintenance
schedule for changing engine oil.
The oil pressure light should come
on briefly as the engine is started.
If it does not come on have the
vehicle serviced by your dealer.
If the light comes on and stays on, it
means that oil is not flowing through
the engine properly. The vehicle
could be low on oil and might have
some other system problem. See
your dealer.
For vehicles with the uplevel or
eAssist cluster, this telltale displays
in the Driver Information Center
(DIC) screen.
Low Fuel Warning Light
This light, below the fuel gauge,
comes on briefly when the engine is
started.
If it does not come on have the
vehicle serviced by your dealer.
If the system is working normally,
the indicator light then goes off.
This light also comes on when the
fuel tank is low on fuel. When fuel is
added the light should go off. If it
does not, have your vehicle
serviced.
For vehicles with an uplevel or
eAssist cluster, this telltale displays
in the Driver Information Center
(DIC) screen.

Black plate (31,1)Buick LaCrosse Owner Manual - 2012
Instruments and Controls 5-31
When the remaining oil life is low,
the CHANGE ENGINE OIL SOON
message will appear on the display.
SeeEngine Oil Messages on
page 5‑38. The oil should be
changed as soon as possible. See
Engine Oil on page 10‑9. In addition
to the engine oil life system
monitoring the oil life, additional
maintenance is recommended in the
Maintenance Schedule in this
manual. See Maintenance Schedule
on page 11‑3 for more information.
Remember, the Oil Life display must
be reset after each oil change. It will
not reset itself. Also, be careful not
to reset the Oil Life display
accidentally at any time other than
when the oil has just been changed.
It cannot be reset accurately until
the next oil change. To reset the
engine oil life system, press SET/
CLR while the Oil Life display is
active. See Engine Oil Life System
on page 10‑12. Battery Voltage
This display, available on some
vehicles, shows the current battery
voltage. If the voltage is in the
normal range, the value will display.
For example, the display may read
Battery Voltage 15.0 Volts. The
vehicle's charging system regulates
voltage based on the state of the
battery. The battery voltage can
fluctuate while viewing this
information on the DIC. This is
normal. See
Charging System Light
on page 5‑17 for more information.
If there is a problem with the battery
charging system, the DIC will
display a message
Compass
The vehicle may have a compass
display in the Driver Information
Center (DIC). See Compass on
page 5‑5 for more information.
Head-Up Display (HUD)
{WARNING
If the HUD image is too bright or
too high in your field of view, it
may take you more time to see
things you need to see when it is
dark outside. Be sure to keep the
HUD image dim and placed low in
your field of view.
For vehicles with the Head-Up
Display (HUD), some information
concerning the operation of the
vehicle is projected onto the
windshield. This includes the
speedometer reading, rpm reading,
transmission position, outside air
temperature, compass heading, and
a brief display of the current radio
station, including XM information or
CD track. It will also display
turn-by-turn navigation information if
the vehicle has a navigation radio.

Black plate (38,1)Buick LaCrosse Owner Manual - 2012
5-38 Instruments and Controls
Engine Oil Messages
CHANGE ENGINE OIL SOON
This message displays when the
engine oil needs to be changed.
When you change the engine oil, be
sure to reset the Oil Life System.
SeeEngine Oil Life System on
page 10‑12 andDriver Information
Center (DIC) on page 5‑27 for
information on how to reset the
system. See Engine Oil on
page 10‑9 andMaintenance
Schedule on page 11‑3 for more
information.
ENGINE OIL HOT, IDLE
ENGINE
This message displays when the
engine oil temperature is too hot.
Stop and allow the vehicle to idle
until it cools down.
ENGINE OIL LOW —ADD OIL
This message displays when the
engine oil level is too low. Check the
oil level. See Engine Oil on
page 10‑9.
OIL PRESSURE LOW —STOP
ENGINE
This message displays if low oil
pressure levels occur. Stop the
vehicle as soon as safely possible
and do not operate it until the cause
of the low oil pressure has been
corrected. Check the oil as soon as
possible and have the vehicle
serviced by your dealer.
Engine Power Messages
ENGINE POWER IS REDUCED
This message displays when the
vehicle's engine power is reduced.
Reduced engine power can affect
the vehicle's ability to accelerate.
If this message is on, but there is no
reduction in performance, proceed
to your destination. The
performance may be reduced the
next time the vehicle is driven. The
vehicle may be driven at a reduced
speed while this message is on, but
maximum acceleration and speed
may be reduced. Anytime this
message stays on, the vehicle
should be taken to your dealer for
service as soon as possible.

Black plate (1,1)Buick LaCrosse Owner Manual - 2012
Climate Controls 8-1
Climate Controls
Climate Control Systems
Automatic Climate ControlSystem . . . . . . . . . . . . . . . . . . . . . . 8-1
Dual Automatic Climate Control System . . . . . . . . . . . . . . . . . . . . . . 8-5
Air Vents
Air Vents . . . . . . . . . . . . . . . . . . . . . 8-10
Maintenance
Air Intake . . . . . . . . . . . . . . . . . . . . 8-11
Passenger Compartment AirFilter . . . . . . . . . . . . . . . . . . . . . . . . 8-11
Climate Control Systems
Automatic Climate Control System
For vehicles with this system, it controls the heating, cooling, and ventilation.
A. Power
B. Temperature Control
C. Fan Control
D. Air Delivery Mode Control
E. Recirculation F. AUTO (Automatic Operation)
G. Defrost
H. Air Conditioning
I. Rear Window Defogger

Black plate (11,1)Buick LaCrosse Owner Manual - 2012
Climate Controls 8-11
Operation Tips
.Keep all outlets open whenever
possible for best system
performance.
.Keep the path under all seats
clear of objects to help circulate
the air inside the vehicle more
effectively.
.Use of non-GM approved hood
deflectors can adversely affect
the performance of the system.
Maintenance
Air Intake
Clear away any ice, snow, or leaves
from the air intake at the base of the
windshield that can block the flow of
air into the vehicle.
Passenger Compartment
Air Filter
The filter removes dust, pollen, and
other airborne irritants from outside
air that is pulled into the vehicle.
The filter should be replaced as part
of routine scheduled maintenance.
SeeMaintenance Schedule on
page 11‑3 for replacement intervals.
For more information, see your
dealer.

Black plate (4,1)Buick LaCrosse Owner Manual - 2012
9-4 Driving and Operating
Control of a Vehicle
Braking, steering, and accelerating
are important factors in helping to
control a vehicle while driving.
Braking
Braking action involves perception
time and reaction time. Deciding to
push the brake pedal is perception
time. Actually doing it is
reaction time.
Average driver reaction time is
about three‐fourths of a second. In
that time, a vehicle moving at
100 km/h (60 mph) travels 20 m
(66 ft), which could be a lot of
distance in an emergency.Helpful braking tips to keep in mind
include:
.Keep enough distance between
you and the vehicle in front
of you.
.Avoid needless heavy braking.
.Keep pace with traffic.
If the engine ever stops while the
vehicle is being driven, brake
normally but do not pump the
brakes. Doing so could make the
pedal harder to push down. If the
engine stops, there will be some
power brake assist but it will be
used when the brake is applied.
Once the power assist is used up, it
can take longer to stop and the
brake pedal will be harder to push.
Steering
Electric Power Steering
If your vehicle has electric power
steering it does not have power
steering fluid. Regular maintenance
is not required.
If power steering assist is lost due
to a system malfunction, the vehicle
can be steered, but may require
increased effort.
If the steering wheel is turned in
either direction several times until it
stops, or it is held until it is stopped
for an extended time, power
steering assist should return shortly
after a few normal steering
movements.
See specific vehicle steering
messages under Vehicle Messages
on page 5‑35.
See your dealer if there is a
problem.