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:Modi cations 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.Modi cations 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 5-4.
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 mis re condition has been
detected. A mis re 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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Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel.
SeeGasoline 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,
mis ring, 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.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.
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