2013 BUICK LACROSSE Emission controls

Black plate (16,1)Buick LaCrosse Owner Manual - 2013 - crc - 9/7/12
5-16 Instruments and Controls
The light turns off when the engine
is started. If it does not, have the
vehicle serviced by your dealer.
If the light stays on, or comes on
while driving, there could be a
problem with the electrical charging
system. Have it checked by your
dealer. Driving while this light is on
could drain the battery.
If a short distance must be driven
with the light on, be sure to turn off
all accessories, such as the radio
and air conditioner.
Malfunction
Indicator Lamp
A computer system called OBD II
(On-Board Diagnostics-Second
Generation) monitors the operation
of the vehicle to ensure emissions
are at acceptable levels, helping to
maintain a clean environment.
The malfunction indicator lamp
comes on when the vehicle is
placed in ON/RUN for key access or
Service Only Mode for keylessaccess, as a check to show it is
working. If it does not, have the
vehicle serviced by your dealer. See
Ignition Positions (Keyless Access)
on page 9‑15
orIgnition Positions
(Key Access) on page 9‑17 for more
information.
If the malfunction indicator lamp
comes on while the engine is
running, this indicates that the OBD
II system has detected a problem
and diagnosis and service might be
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 also
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.

Black plate (17,1)Buick LaCrosse Owner Manual - 2013 - crc - 9/7/12
Instruments and Controls 5-17
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, find a
safe place to stop and park the
vehicle. 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.
The following may correct an
emissions control system
malfunction:
.Check that the fuel cap is fully
installed. See Filling the Tank on
page 9‑50. 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 may require at least one full tank
of the proper fuel to turn the light off.
See Recommended Fuel on
page 9‑47.
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
Depending on where you live, your
vehicle may be required to
participate in an emission control
system inspection and maintenance
program. For the inspection, the
emission system test equipment will
likely connect to the vehicle's Data
Link Connector (DLC).

Black plate (18,1)Buick LaCrosse Owner Manual - 2013 - crc - 9/7/12
5-18 Instruments and Controls
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.
.The OBD II (On-Board
Diagnostics) system determines
that critical emission control
systems have not been
completely diagnosed. Thevehicle would be considered not
ready for inspection. This can
happen if the 12-volt battery has
recently been replaced or run
down. The diagnostic system is
designed to evaluate critical
emission control systems during
normal driving. This can take
several days of routine driving.
If this has been done and the
vehicle still does not pass the
inspection for lack of OBD II
system readiness, your dealer
can prepare the vehicle for
inspection.
Brake System Warning
Light
The vehicle brake system consists
of two hydraulic circuits. If one
circuit is not working, the remaining
circuit can still work to stop the
vehicle. For normal braking
performance, both circuits need to
be working.
If the warning light comes on, there
is a brake problem. Have your brake
system inspected right away.
MetricEnglish
With antilock brakes, this light
should come on when the vehicle is
placed in START. If it does not, have
the vehicle serviced by your dealer.
If the light comes on while driving,
pull off the road and stop carefully.
The pedal may be harder to push or
it can go closer to the floor. It may
take longer to stop. Try turning off
and restarting the vehicle one or two
times. If the light is still on, have the
vehicle towed for service. See
Antilock Brake System (ABS)
Warning Light on page 5‑19 and
Towing the Vehicle on page 10‑90.