2008 BUICK LUCERNE service

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, there is a brake problem.
Have your brake system inspected right away.
This light should come on briey when you start the
engine. If it does not come on then, have it xed so it will
be ready to warn you if there is a problem.
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, 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 4-25.
{CAUTION:
Your brake system may not be working
properly if the brake system warning light is
on. Driving with the brake system warning light
on can lead to an accident. If the light is still
on after you have pulled off the road and
stopped carefully, have the vehicle towed for
service. United States
Canada
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Antilock Brake System
Warning Light
For vehicles with the
Antilock Brake System
(ABS), this light will come
on briey when you
start the engine.
That is normal. If the light does not come on then, have it
xed so it will be ready to warn you if there is a problem.
If the ABS light stays on, turn the ignition off, if the light
comes on when you are 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 still
stays on, or comes on again while you are driving, your
vehicle needs service. If the regular brake system
warning light is not on, you still have brakes, but you do
not have antilock brakes. If the regular brake system
warning light is also on, you do not have antilock brakes
and there is a problem with your regular brakes. See
Brake System Warning Light on page 3-39
For vehicles with a Driver Information Center (DIC), see
DIC Warnings and Messages on page 3-56for all
brake related DIC messages.
Traction Control System (TCS)
Warning Light
This warning light should
come on briey when the
engine is started.
If the warning light does not come on then, have it xed
so it will be ready to warn you if there is a problem. If
it stays on, or comes on when you are driving a
SERVICE TRACTION CONTROL message will appear
in the Driver Information Center (DIC). This indicates
that there may be a problem with your traction control
system and your vehicle may need service. When
this warning light is on and the SERVICE TRACTION
CONTROL message appears on the DIC, the system
will not limit wheel spin. Adjust your driving accordingly.
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If the traction control system is manually turned off, this
light will come on and the TRACTION CONTROL OFF
message will appear on the DIC. When the system is
active, the light will ash while the system is limiting
wheel spin or assisting you in controlling the vehicle. You
may also feel or hear the system working. This is normal.
SeeTraction Control System (TCS) on page 4-5and
DIC Warnings and Messages on page 3-56for
more information.
StabiliTrak®Indicator Light
This warning light should
come on briey when the
engine is started.
If the warning light does not come on then, have it xed
so it will be ready to warn you if there is a problem.
This light may come on after you rst start to drive and
the STABILITRAK NOT READY message will appear
in the Driver Information Center (DIC). SeeStabiliTrak
®
System on page 4-6for more information.If the light stays on, or comes on when you are driving
a SERVICE STABILITRAK message will appear in
the DIC. This indicates that there may be a problem with
the StabiliTrak
®system and your vehicle may need
service. When this warning light is on and the SERVICE
STABILITRAK message appears on the DIC, the
system will not assist you in controlling the vehicle.
Adjust your driving accordingly.
When the system is active, the light will ash while the
system is assisting you in controlling the vehicle. You
may also feel or hear the system working. This is normal.
SeeStabiliTrak
®System on page 4-6andDIC Warnings
and Messages on page 3-56for more information.
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Lane Departure Warning Light
Your vehicle may have the
lane departure warning
system.
This light will come on green, briey, when the vehicle
is started to show that it is working. This light will
also come on green if the system detects a left or right
lane marking. This light will change to amber and
ash and three beeps will sound if you cross a detected
lane marking without using your turn signal. For more
information, see the Index in the Navigation Manual.
Engine Coolant Temperature
Warning Light
The engine coolant
temperature warning light
will come on when the
engine has overheated.
If this happens you should pull over and turn off the
engine as soon as possible. SeeEngine Overheating on
page 5-28for more information.
Notice:Driving with the engine coolant temperature
warning light on could cause your vehicle to
overheat. SeeEngine Overheating on page 5-28.
Your vehicle could be damaged, and it might not be
covered by your warranty. Never drive with the
engine coolant temperature warning light on.
This light will also come on briey when starting your
vehicle. If it does not, have your vehicle serviced.
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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 makes
sure that emissions are at acceptable levels for the life of
the vehicle, helping to produce a cleaner environment.
The check engine light
comes on to indicate that
there is an OBD II
problem and service is
required.
Malfunctions often are indicated by the system before
any problem is apparent. This can 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 a while, the emission controls
might not work as well, your 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 your warranty.Notice:Modications made to the engine,
transmission, 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 can cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This could
also result in a failure to pass a required Emission
Inspection/Maintenance test. SeeAccessories
and Modifications on page 5-3.
This light comes on, as a check to show it is working,
when the ignition is turned ON/RUN but the engine is not
running. If the light does not come on, have it repaired.
This light also 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
your vehicle. Diagnosis and service might be
required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service might be required.
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If the Light is Flashing
The following can prevent more serious damage to your
vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid steep uphill grades.
If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible.
If 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 the vehicle.
Turn the ignition 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/retailer
for service as soon as possible.
If the Light Is On Steady
You might 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 missingfuel cap allows fuel to evaporate into the atmosphere. A
few driving trips with the cap properly installed should
turn the light off.
Did you just drive through a deep puddle of water?
If so, your 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.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-6. Poor fuel quality causes
the engine not to run as efficiently as designed. You
might 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 might 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/retailer can check the vehicle. Your
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 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 the battery 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 you have done this and your vehicle
still does not pass the inspection for lack of OBD
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. 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.
This light will come on
briey when you start your
engine. If it does not,
have your vehicle serviced.
When the light comes on and stays on, it means that oil
is not owing through your engine properly. You
could be low on oil and you might have some other
system problem.
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Fuel Gage
The fuel gage shows about how much fuel is in your
tank. It works only when the ignition is on. When
the indicator moves to the edge of the low fuel warning
band, the low fuel warning light will come on and a
chime will sound. You still have a little fuel left, but you
need to get more fuel right away.Here are some things that some owners ask about.
None of these show a problem with your fuel gage:
At the service station, the gas pump shuts off before
the gage reads full.
It takes more (or less) fuel to ll up than the gage
indicated. For example, the gage may have
indicated half full, but it took more (or less) than
half the tank’s capacity to ll it.
The gage moves up a little when you turn a corner,
speed up or make a hard stop.
The gage does not go back to empty when you turn
off the ignition.
Driver Information Center (DIC)
Your vehicle has a Driver Information Center (DIC).
All messages will appear in the DIC display located
below the speedometer in the instrument panel cluster.
The DIC buttons are located on the instrument panel,
to the left of the instrument panel cluster.
The DIC comes on when the ignition is on. After a short
delay, the DIC will display the information that was
last displayed before the engine was turned off. United States
Canada
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