check engine BUICK LACROSSE 2009 User Guide

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.
3-40

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.
3-41

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.
3-42

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.
3-57

CHECK GAS CAP
This message may display if the fuel cap is not on, or is
not fully tightened. The check gas cap light also appears
on the instrument panel cluster. SeeCheck Gas Cap
Light on page 3-47. Check the fuel cap to ensure that it is
on properly. 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 this message off. SeeFilling the
Tank on page 5-8for more information.
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.
CHECK TIRE PRESSURE
On vehicles with the Tire Pressure Monitor System
(TPMS), this message displays when the pressure in one
or more of the vehicle’s tires needs to be checked. This
message also displays LEFT FRONT, RIGHT FRONT,
LEFT REAR, or RIGHT REAR to indicate which tire
needs to be checked. You can receive more than one tire
pressure message at a time. To read the other messages
that may have been sent at the same time, press the
set/reset button. If a tire pressure message appears on
the DIC, stop as soon as you can. Have the tire pressures
checked and set to those shown on the Tire Loading
Information label. SeeTires on page 5-54,Loading the
Vehicle on page 4-20, andInflation - Tire Pressure on
page 5-61. The DIC also shows the tire pressure values.
SeeDIC Operation and Displays on page 3-48. If the tire
pressure is low, the low tire pressure warning light comes
on. SeeTire Pressure Light on page 3-39.
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.
3-58

SERVICE PARK LAMPS
This message displays when there is a problem with the
park lamps. Check to see if the park lamp fuse is blown
and replace the fuse if necessary. SeeFuses and Circuit
Breakers on page 5-99andInstrument Panel Fuse Block
on page 5-100for more information. If changing the fuse
does not correct the problem, see your dealer/retailer.
This message only 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.
SERVICE STABILITY SYSTEM
If your vehicle has StabiliTrak, this message displays if
there has been a problem detected with StabiliTrak.
A warning light also appears on the instrument panel
cluster. SeeTraction Control System (TCS) Warning
Light on page 3-37. SeeStabiliTrak
®System on
page 4-6for more information.
If this message turns 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 and then
back on. If this message still stays on or turns back on
again while you are driving, your vehicle needs service.
Have the StabiliTrak System inspected by your dealer/
retailer as soon as possible.
This message displays only 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.
3-69

Antilock Brake System (ABS)
This vehicle has the Antilock Brake System (ABS), an
advanced electronic braking system that will help
prevent a braking skid.
When the engine is started and the vehicle begins to
drive away, ABS checks itself. A momentary motor
or clicking noise might be heard while this test is going
on, and it might even be noticed that the brake pedal
moves a little. This is normal.
If there is a problem with
ABS, this warning light
stays on. SeeAntilock
Brake System (ABS)
Warning Light on
page 3-36.
Let us say the road is wet and you are driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. Here is what
happens with ABS:
A computer senses that the wheels are slowing down. If
one of the wheels is about to stop rolling, the computer
will separately work the brakes at each wheel.ABS can change the brake pressure to each wheel, as
required, faster than any driver could. This can help
the driver steer around the obstacle while braking hard.
As the brakes are applied, the computer keeps receiving
updates on wheel speed and controls braking pressure
accordingly.
Remember: ABS does not change the time needed to get
a foot up to the brake pedal or always decrease stopping
distance. If you get too close to the vehicle in front of you,
there will not be enough time to apply the brakes if that
vehicle suddenly slows or stops. Always leave enough
room up ahead to stop, even with ABS.
Using ABS
Do not pump the brakes. Just hold the brake pedal
down rmly and let antilock work. The antilock pump or
motor might be heard operating and the brake pedal
might be felt to pulsate, but this is normal.
Braking in Emergencies
ABS allows the driver to steer and brake at the same
time. In many emergencies, steering can help more than
even the very best braking.
4-5

Before Leaving on a Long Trip
To prepare your vehicle for a long trip, consider having
it serviced by your dealer/retailer before departing.
Things to check on your own include:
Windshield Washer Fluid:Reservoir full? Windows
clean — inside and outside?
Wiper Blades:In good shape?
Fuel, Engine Oil, Other Fluids:All levels checked?
Lamps:Do they all work and are lenses clean?
Tires:Are treads good? Are tires inated to
recommended pressure?
Weather and Maps:Safe to travel? Have
up-to-date maps?
Highway Hypnosis
Always be alert and pay attention to your surroundings
while driving. If you become tired or sleepy, nd a
safe place to park your vehicle and rest.
Other driving tips include:
Keep the vehicle well ventilated.
Keep interior temperature cool.
Keep your eyes moving — scan the road ahead
and to the sides.
Check the rearview mirror and vehicle instruments
often.
4-15