2005 BUICK LACROSSE Owner's Manual

Low Coolant Warning Light
If equipped, this light
comes on briey when you
turn your ignition on as
a bulb check only.
Malfunction Indicator Lamp
Check Engine Light
Your vehicle is equipped
with a computer which
monitors operation of the
fuel, ignition, and emission
control systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for thelife of the vehicle, helping to produce a cleaner
environment. The check engine light comes on to
indicate that there is a problem and service is required.
Malfunctions often will be indicated by the system
before any problem is apparent. This may prevent more
serious damage to your vehicle. This system is also
designed to assist your service technician in correctly
diagnosing any malfunction.
Notice:If you keep driving your vehicle with this
light on, after awhile, your emission controls
may not work as well, your fuel economy may not
be as good, and your engine may not run as
smoothly. This could lead to costly repairs that may
not be covered by your warranty.
Notice:Modications made to the engine,
transaxle, exhaust, intake, or fuel system of your
vehicle or the replacement of the original tires with
other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and may cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This may
also result in a failure to pass a required Emission
Inspection/Maintenance test.
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This light should come on, as a check to show you it is
working, when the ignition is on and the engine is
not running. If the light does not come on, have it
repaired. This light will also come on during a
malfunction in one of two ways:
Light Flashing— A misre condition has been
detected. A misre increases vehicle emissions
and may damage the emission control system on
your vehicle. Diagnosis and service may be
required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
If the Light is Flashing
The following may prevent more serious damage to
your vehicle:
Reducing vehicle speed
Avoiding hard accelerations
Avoiding steep uphill grades
If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possibleIf the light stops ashing and remains on steady, see “If
the Light Is On Steady” following.
If the light continues to ash, when it is safe to do so,
stop the vehicle. Find a safe place to park your vehicle.
Turn the key off, wait at least 10 seconds and restart
the engine. If the light remains on steady, see “If
the Light Is On Steady” following. If the light is still
ashing, follow the previous steps, and see your dealer
for service as soon as possible.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install
the cap. 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 will allow fuel to evaporate into the atmosphere.
A few driving trips with the cap properly installed
should turn the light off.
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Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-5. Poor fuel quality will
cause your engine not to run as efficiently as designed.
You may notice this as stalling after start-up, stalling
when you put the vehicle into gear, misring, hesitation
on acceleration, or stumbling on acceleration. (These
conditions may go away once the engine is warmed up.)
This will be detected by the system and cause the
light to turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
your dealer can check the vehicle. Your dealer has
the proper test equipment and diagnostic tools to x any
mechanical or electrical problems that may have
developed.Emissions Inspection and
Maintenance Programs
Some state/provincial and local governments have or
may begin programs to inspect the emission control
equipment on your vehicle. Failure to pass this
inspection could prevent you from getting a vehicle
registration.
Here are some things you need to know to help your
vehicle pass an inspection:
Your vehicle will not pass this inspection if the check
engine light is on or not working properly.
Your vehicle will not pass this inspection if the OBD
(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
you have recently replaced your battery or if your
battery has run down. The diagnostic system is
designed to evaluate critical emission control systems
during normal driving. This may take several days
of routine driving. If you have done this and your vehicle
still does not pass the inspection for lack of OBD
system readiness, your GM dealer can prepare the
vehicle for inspection.
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Oil Pressure Light
If the vehicle has an oil
problem, this light may
stay on after the engine is
started, or come on
while you are driving.
This light indicates that oil is not going through the
engine quickly enough to keep it lubricated. The engine
could be low on oil or could have some other oil
problem. Have it xed right away.
The oil light could also come on in the following
situations:
The light will come on briey when the ignition is
turned on to show that it is working properly. If it
does not come on with the ignition on, there may be
a problem with the fuse or bulb. Have it xed
right away.
Sometimes when the engine is idling at a stop, a
chime will sound and the light may blink on and
off. This is normal.
{CAUTION:
Do not keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be
covered by your warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.
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Change Engine Oil Light
If this light comes on, it
means that service is
required for your vehicle.
SeeScheduled
Maintenance on page 6-4
andEngine 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, see
Theft-Deterrent Systems
on page 2-17.
Cruise Control Light
This light comes on
whenever you set your
cruise control.
The light will go out when the cruise control is
turned off. SeeCruise Control on page 3-10for
more information.
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Reduced Engine Power Light
If the reduced engine
power light is on, a chime
will sound and a
noticeable reduction in the
vehicle’s performance
may occur.
If the reduced engine power light 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 the reduced engine power light is
on, but acceleration and speed may be reduced.
Anytime the reduced engine power light stays on, the
vehicle should be taken to an authorized GM dealer as
soon as possible for service.
Highbeam On Light
This light will come on
when the high-beam
headlamps are in use.
SeeHeadlamp High/Low-Beam Changer on page 3-8.
Headlamps Suggested Light
This light will come on
when the use of
headlamps is suggested.
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Low Washer Fluid Warning Light
This light will come on
briey when the ignition is
on. If the light stays on,
a chime will sound
indicating your windshield
washer uid is low.
SeeWindshield Washer Fluid on page 5-34for more
information.
Door Ajar Light
When the ignition is on,
this light will stay on until
all doors are closed
and completely latched.
You will hear a chime if a door is unlatched after the
engine is started and the vehicle is not in PARK (P).
Trunk Ajar Light
This light will come on and
a chime will sound if the
trunk is ajar and the
vehicle is not in Park (P).
Try closing the trunk
again. Never drive with the
trunk open.
Service Vehicle Soon Light
If equipped, this light will
come on and a chime will
sound if it detects a
problem on the vehicle.
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Fuel Gage
The fuel gage indicates
about how much fuel is left
in the fuel tank when the
ignition is on.
When the indicator nears empty, there is still a little fuel
left, but you should get more fuel soon.
Here are four things that some owners ask about. All
these things are normal and do not indicate that
anything is wrong with the fuel gage:
At the gas station, the pump shuts off before the
gage reads full.
It takes more, or less, fuel to ll up than the gage
reads. For example, the gage reads half full, but
it took more, or less, than half of the tank’s capacity
to ll it.
The gage pointer may move while cornering,
braking or accelerating.
The gage may not indicate empty when the ignition
is turned off.
Low Fuel Warning Light
If the vehicle’s fuel is low, a light on the fuel gage, if
equipped, will come on and a chime will sound
periodically until 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 DIC, a LOW FUEL message will
appear. SeeDIC Warnings and Messages on page 3-53
for more information.
Check Gas Cap Light
If equipped, this light will
come on and a chime will
sound if your gas cap
is not securely fastened.
SeeMalfunction Indicator Lamp on page 3-39for more
information.
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