2009 BUICK LACROSSE service

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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When the ignition is on, the brake system warning
light will also come on when you set your parking brake.
The light will stay on if your parking brake does not
release fully. If it stays on after your parking brake is
fully released, it means you have a brake problem.
If the light comes on while you are driving, a chime will
sound and you should pull off the road and stop carefully.
You may notice that the pedal is harder to push. Or, the
pedal may go closer to the oor. It may take longer to
stop. If the light is still on, have the vehicle towed for
service. SeeTowing Your Vehicle on page 4-26.
{CAUTION:
The brake system might not be working properly if
the brake system warning light is on. Driving with
the brake system warning light on can lead to a
crash. If the light is still on after the vehicle has
been pulled off the road and carefully stopped,
have the vehicle towed for service.
Antilock Brake System (ABS)
Warning Light
For vehicles with
the Antilock Brake
System (ABS), this light
comes on briey when
the engine is started.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally the
indicator light then goes off.
If the ABS light stays on, turn the ignition off. If the
light comes on while driving, stop as soon as it is safely
possible and turn the ignition off. Then start the engine
again to reset the system. If the ABS light stays on, or
comes on again while driving, the vehicle needs service.
If the regular brake system warning light is not on, the
vehicle still has brakes, but not antilock brakes. If the
regular brake system warning light is also on, the vehicle
does not have antilock brakes and there is a problem with
the regular brakes. SeeBrake System Warning Light on
page 3-35.
For vehicles with a Driver Information Center (DIC),
seeDIC Warnings and Messages on page 3-56for
all brake related DIC messages.
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Traction Control System (TCS)
Warning Light
Your vehicle has
a Traction Control
System (TCS)
warning light.
If this warning light comes on and stays on, there may
be a problem with the TCS and, if your vehicle has
this feature, the StabiliTrak
®system.
The TCS warning light will come on briey when the
engine is started. If it does not come on then, have it xed
so it will be ready to warn you if there is a problem. This
light will also come on when the traction control button is
pressed disabling the system.
If the TCS warning light stays on or comes on while you
are driving, pull off the road as soon as possible and stop
carefully. Try resetting the system by turning the ignition
off then back on. If the light still stays on or comes back
on again while you are driving, your vehicle needs
service. Have the traction control system and, if your
vehicle has this feature, the StabiliTrak
®systeminspected as soon as possible. SeeTraction Control
System (TCS) on page 4-7andStabiliTrak
®System on
page 4-6for more information.
Enhanced Traction System
Warning Light
For vehicles with the
Enhanced Traction
System (ETS), this light
may come on for the
following reasons:
If the traction control button located on the instrument
panel is pressed, turning the system off. This light will
come on and stay on. To turn the system back on,
press the button again and the warning light should
turn off. SeeEnhanced Traction System (ETS) on
page 4-8.
If the system is affected by an engine-related
problem, the system will turn off and the warning
light will come on.
If the light comes on and stays on for an extended
period of time when the system is turned on, the vehicle
needs service.
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Engine Coolant Temperature
Warning Light
This light comes on briey
while starting the vehicle.
If it does not, have the vehicle serviced by the
dealer/retailer. If the system is working normally the
indicator light goes off.
Notice:Driving with the engine coolant temperature
warning light on could cause the vehicle to overheat.
SeeEngine Overheating on page 5-31. The vehicle’s
engine could be damaged, and it might not be
covered by the vehicle warranty. Never drive with
the engine coolant temperature warning light on.
The engine coolant temperature warning light comes on
when the engine has overheated.
If this happens pull over and turn off the engine as soon
as possible. SeeEngine Overheating on page 5-31
for more information.
Engine Coolant Temperature Gage
The vehicle has a gage
that shows the engine
coolant temperature.
If the gage pointer moves towards the H, the engine is
too hot.
This reading indicates the same thing as the warning
light. It means that the engine coolant has overheated.
If the vehicle has been operating under normal driving
conditions, pull off the road, stop the vehicle, and turn off
the engine as soon as possible. SeeEngine Overheating
on page 5-31.
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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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This light comes on briey while starting the engine.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally
the indicator light then goes off.
If the light comes on and stays on, it means that oil is
not owing through the engine properly. The vehicle
could be low on oil and it might have some other system
problem.
Change Engine Oil Light
If this light comes on,
it means that service is
required for your vehicle.
SeeScheduled Maintenance on page 6-4andEngine
Oil on page 5-15for more information.
After having the oil changed you will need to reset the
light. SeeEngine Oil on page 5-15for more information.
If this light is blinking, a chime will sound indicating
low engine oil.
Security Light
For information regarding
this light and the vehicle’s
security system, see
Content Theft-Deterrent
on page 2-17.
Cruise Control Light
The cruise control light
comes on whenever the
cruise control is set.
The light goes out when the cruise control is turned off.
SeeCruise Control on page 3-10for more information.
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