2009 CHEVROLET IMPALA check engine

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.
SeeAccessories and Modifications on page 5-3.
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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.
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.
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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.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.
Security Light
For information regarding
this light and the vehicle’s
security system, see
Content Theft-Deterrent
on page 2-16.
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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 5-20.
Units
Press the vehicle information button until UNITS
displays. This display allows you to select between
English or Metric units of measurement. Once in this
display, press the set/reset button to select between
ENGLISH or METRIC units.
Tire Pressure
On vehicles with the Tire Pressure Monitor
System (TPMS), the pressure for each tire can be
viewed in the DIC. The tire pressure will be shown in
either pounds per square inch (psi) or kilopascals (kPa).
Press the vehicle information button until the DIC
displays FRONT TIRES PSI (kPa) LEFT ## RIGHT ##.
Press the vehicle information button again until the
DIC displays REAR TIRES PSI (kPa) LEFT ##
RIGHT ##.If a low or high 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 5-60andDIC
Warnings and Messages on page 3-49for more
information.
If the tire pressure display shows dashes instead of
a value, there may be a problem with your vehicle. If this
consistently occurs, see your dealer/retailer for service.
Change Compass Zone
Your vehicle may have this feature. To change the
compass zone through the DIC, seeDIC Compass
on page 3-47.
Calibrate Compass
Your vehicle may have this feature. The compass
can be manually calibrated. To calibrate the compass
through the DIC, seeDIC Compass on page 3-47.
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AUTOMATIC LIGHT CONTROL ON
This message displays when the automatic headlamps
are turned on. SeeExterior Lamps on page 3-12for
more information.
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.
CHANGE ENGINE OIL SOON
This message displays when service is required for the
vehicle. See your dealer/retailer. SeeEngine Oil on
page 5-17andScheduled Maintenance on page 6-4
for more information.
Acknowledging the CHANGE ENGINE OIL SOON
message will not reset the OIL LIFE REMAINING.That must be done at the OIL LIFE screen under the
vehicle information menu. See “Oil Life” underDIC
Operation and Displays on page 3-42andEngine Oil
Life System on page 5-20.
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 5-53,
Loading the Vehicle on page 4-20, andInflation - Tire
Pressure on page 5-60. The DIC also shows the tire
pressure values. SeeDIC Operation and Displays on
page 3-42. If the tire pressure is low, the low tire pressure
warning light comes on. SeeTire Pressure Light on
page 3-35.
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SERVICE TRACTION CONTROL
If your vehicle has the Traction Control System (TCS),
this message displays when the system is not functioning
properly. A warning light also appears on the instrument
panel cluster. SeeTraction Control System (TCS)
Warning Light on page 3-32. SeeTraction Control
System (TCS) on page 4-8for more information.
Have the TCS serviced by your dealer/retailer as
soon as possible.
SERVICE TRANSMISSION
This message displays when there is a problem with the
transmission. See your dealer/retailer for service.
SERVICE VEHICLE SOON
This message displays when a non-emissions related
malfunction occurs. Have the vehicle serviced by
your dealer/retailer as soon as possible.
STABILITRAK NOT READY
If your vehicle has Electronic Stability Control (ESC),
this message may display and the ESC/TCS light on the
instrument panel cluster may be on after rst driving the
vehicle and exceeding 19 mph (30 km/h) for 30 seconds.
The ESC system is not functional until the light has turned
off. SeeElectronic Stability Control (ESC) on page 4-6for
more information.
STARTING DISABLED SERVICE
THROTTLE
This message displays if the starting of the engine is
disabled due to the electronic throttle control system.
Have your vehicle serviced by your dealer/retailer
immediately.
This message only appears while the ignition is in
ON/RUN, and will not disappear until the problem is
resolved.
This message cannot be acknowledged.
THEFT ATTEMPTED
This message displays if the content theft-deterrent
system has detected a break-in attempt while you were
away from your vehicle. SeeContent Theft-Deterrent
on page 2-16for more information.
TIGHTEN GAS CAP
This message may be displayed if the gas cap is not
on, or is not fully tightened. Check the gas cap to ensure
that it is on properly. SeeFilling the Tank on page 5-10
for more information.
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Antilock Brake System (ABS)
The vehicle might have the Antilock Brake System
(ABS), an advanced electronic braking system that helps
prevent a braking skid.
If the vehicle has ABS,
this warning light on the
instrument panel cluster
comes on briey when the
vehicle is started.
When the engine is started, or when 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 or pulses a little. This is normal.
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 front wheel
and at both rear wheels.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. A slight brake pedal
pulsation might be felt or some noise might be
heard, but this is normal.
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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.
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