2009 BUICK LACROSSE check engine

Charging System Light
This light comes on briey
when the ignition key is
turned to START, but the
engine is not running, as a
check to show it is working.
If it does not, have the vehicle serviced by your
dealer/retailer.
The light should go out once the engine starts. If it stays
on, or comes on while driving, there could be a problem
with the charging system. A charging system message
in the Driver Information Center (DIC) can also appear.
SeeDIC Warnings and Messages on page 3-56for
more information. This light could indicate that there
are problems with a generator drive belt, or that there
is an electrical problem. Have it checked right away.
If the vehicle must be driven a short distance with the
light on, turn off accessories, such as the radio and air
conditioner.
Brake System Warning Light
Your vehicle’s hydraulic brake system is divided into
two parts. If one part is not working, the other part can
still work and stop you. For good braking, though,
you need both parts working well.
If the warning light comes on and the parking brake
is not applied, there is a brake problem. Have your
brake system inspected right away.
This light should come on
briey when you turn the
ignition key to ON/RUN.
If it does not come on then, have it xed so it will be
ready to warn you if there is a problem.
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Low Coolant Warning Light
If your vehicle has this
light, it comes on briey
when you turn your ignition
on as a bulb check only.
Tire Pressure Light
For vehicles with a tire
pressure light, this light
comes on briey when
the engine is started and
provides information about
tire pressures and the
Tire Pressure Monitoring
System.
When the Light is On Steady
This indicates that one or more of the tires is signicantly
underinated.
A tire pressure message in the Driver Information
Center (DIC), can accompany the light. SeeDIC
Warnings and Messages on page 3-56for more
information. Stop and check the tires as soon as it
is safe to do so. If a tire is underinated, inate to the
proper pressure. SeeTires on page 5-54for more
information.
When the Light Flashes First and Then is
On Steady
This indicates that there could be a problem with the
Tire Pressure Monitor System. The light ashes for about
a minute and stays on steady for the remainder of the
ignition cycle. This sequence repeats with every ignition
cycle. SeeTire Pressure Monitor System on page 5-62
for more information.
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Malfunction Indicator Lamp
Check Engine Light
A computer system called OBD II (On-Board
Diagnostics-Second Generation) monitors operation
of the fuel, ignition, and emission control systems.
It ensures that emissions are at acceptable levels for
the life of the vehicle, helping to produce a cleaner
environment.
This light should come on
when the ignition is on, but
the engine is not running,
as a check to show it
is working. If it does not,
have the vehicle serviced
by your dealer/retailer.
If the check engine light 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 service technician in correctly
diagnosing any malfunction.
Notice:If the vehicle is continually driven with
this light on, after a while, the emission controls
might not work as well, the vehicle’s 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:Modications 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.
Modications 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 5-3.
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This light comes on during a malfunction in one of
two ways:
Light Flashing:A misre condition has been detected.
A misre 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 towing a trailer, reduce the amount of cargo being
hauled as soon as it is possible.
If the light continues to ash, when it is safe to do so,
stop the vehicle. Find a safe place to park the vehicle.
Turn the key off, wait at least 10 seconds, and restart
the engine. If the light is still ashing, follow the previous
steps and see your dealer/retailer 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.An emission system malfunction might be corrected by
doing the following:
Make sure the fuel cap is fully installed. SeeFilling
the Tank on page 5-8. 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.
If the vehicle has been driven through a deep puddle
of water, the vehicle’s electrical system might be wet.
The condition is usually corrected when the electrical
system dries out. A few driving trips should turn the
light off.
Make sure to fuel the vehicle with quality fuel. Poor
fuel quality causes the engine not to run as efficiently
as designed and can cause: stalling after start-up,
stalling when the vehicle is changed into gear,
misring, 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.
SeeGasoline Octane on page 5-6.
If none of the above have made the light turn off, your
dealer/retailer can check the vehicle. The dealer/retailer
has the proper test equipment and diagnostic tools to
x any mechanical or electrical problems that might have
developed.
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Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
might begin programs to inspect the emission control
equipment on the vehicle. Failure to pass this inspection
could prevent getting a vehicle registration.
Here are some things to know to help the vehicle pass
an inspection:
The vehicle will not pass this inspection if the check
engine light is on with the engine running, or if the
key is in ON/RUN and the light is not on.
The vehicle will not pass this inspection if the OBD
II (on-board diagnostic) system determines that
critical emission control systems have not been
completely diagnosed by the system. The vehicle
would be considered not ready for inspection. This
can happen if the battery has recently been replaced
or if the battery has 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/retailer can
prepare the vehicle for inspection.
Oil Pressure Light
{CAUTION:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches re.
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 in this manual for
changing engine oil.
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Low Fuel Warning Light
Your vehicle may have a low fuel light. It is a circle
located on the fuel gage and will come on and a chime
will sound periodically when the vehicle is low on fuel.
The light will go off when fuel is added to the fuel tank.
It will also come on for a few seconds when the ignition
is turned on as a check to indicate it is working. If it
does not come on then, have it xed.
For vehicles with a Driver Information Center (DIC), a
LOW FUEL message will appear. SeeDIC Warnings
and Messages on page 3-56for more information.
Check Gas Cap Light
If your vehicle has this
light, it will come on if your
gas cap is not securely
fastened.
SeeMalfunction Indicator Lamp on page 3-40for more
information.
Driver Information Center (DIC)
Your vehicle may have a Driver Information
Center (DIC).
All messages will appear in the DIC display located in
the instrument panel cluster, below the speedometer.
The DIC buttons are located on the center of the
instrument panel, below the center outlets.
The DIC comes on when the ignition is on. After a
short delay, the uplevel DIC will display the WELCOME
DRIVER (1 or 2) if a personalized key 1 or 2 is used, and
then the information that was last displayed before the
engine was turned off.
The base level DIC displays the odometer and trip
odometers only.
The uplevel DIC displays the odometer, trip odometers,
fuel economy, trip computer, vehicle system, and
compass display information. It also displays warning
messages if a system problem is detected. In addition,
the uplevel DIC displays phone numbers that are
called using the OnStar
®system, if equipped.
SeeOnStar®System on page 2-39.
3-47

Oil Life
Press the gages button until OIL LIFE displays. This
mode shows an estimate of the oil’s remaining useful
life. If you see OIL LIFE 99% on the display, that means
99% of the current oil life remains. The engine oil life
system will alert you to change your oil on a schedule
consistent with your driving conditions.
When the remaining oil life is low, the CHANGE OIL
SOON message will appear on the display. You should
change your oil as soon as possible. SeeEngine Oil
on page 5-15. In addition to the engine oil life system
monitoring the oil life, additional maintenance is
recommended in the Maintenance Schedule in this
manual. SeeScheduled Maintenance on page 6-4
for more information.
Remember, you must reset the OIL LIFE yourself after
each oil change. It will not reset itself. Also, be careful not
to reset the OIL LIFE 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, seeEngine Oil Life System on page 5-18.
The display will show 100% when the system is reset.
Tire Pressure
On vehicles with the Tire Pressure Monitor System
(TPMS), press the gages button until FRONT TIRE
PRESSURE displays. This mode shows the pressure
for the front tires. To view the pressure for the rear
tires, press the gages button again until REAR TIRE
PRESSURE displays. The tire pressure will be shown in
either pounds per square inch (psi) or kilopascals (kPa).
If a low tire pressure condition is detected by the
system while driving, a message advising you to check
the pressure in a specic tire will appear in the display.
SeeInflation - Tire Pressure on page 5-61andDIC
Warnings and Messages on page 3-56for more
information.
If the tire pressure display shows dashes or blanks
instead of a value, there may be a problem with
your vehicle. If this consistently occurs, see your
dealer/retailer for service.
3-52

BATTERY SAVER ACTIVE
This message displays when the system detects that
the battery voltage is dropping beyond a reasonable
level. The battery saver system starts reducing certain
features of the vehicle that you may be able to notice.
At the point that the features are disabled, this message
is displayed. It means that the vehicle is trying to
save the charge in the battery.
Turn off all unnecessary accessories to allow the battery
to recharge.
The normal battery voltage range is 11.5 to 15.5 volts.
If your vehicle has an uplevel DIC, you can monitor
the battery voltage by pressing the gages button until
BATTERY displays.
CHANGE OIL SOON
This message displays when service is required for
the vehicle. See your dealer/retailer. SeeEngine Oil on
page 5-15andScheduled Maintenance on page 6-4for
more information.
The CHANGE OIL SOON message is reset by
acknowledging the message. The OIL LIFE screen
under the gages menu on the DIC must also be reset.
See “Oil Life” underDIC Operation and Displays on
page 3-48andEngine Oil Life System on page 5-18.
This message displays while the ignition is in ON/RUN.
Press any of the DIC buttons to acknowledge this
message and to clear it from the screen.This message continues to display for two seconds
if it has not been acknowledged when the engine
is turned off. It also re-displays for two seconds if the
message has been acknowledged, but the condition
still exists when the engine is turned off.
If the condition still exists, the message re-appears
when the engine is turned on.
CHARGING SYSTEM FAILURE
This message displays when there is a problem with the
generator and battery charging systems. Driving with this
problem could drain the battery. Turn off all unnecessary
accessories. Stop and turn off the vehicle as soon as it is
safe to do so. Have the electrical system checked by your
dealer/retailer immediately.
This message displays and a chime sounds while the
ignition is in ON/RUN. Press any of the DIC buttons
to acknowledge this message and to clear it from the
screen.
This message continues to display for two seconds
if it has not been acknowledged when the engine
is turned off. It also re-displays for two seconds if the
message has been acknowledged, but the condition
still exists when the engine is turned off.
If the condition still exists, the message re-appears
when the engine is turned on.
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