Cadillac 2011 STS, Owner'S Manual

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Black plate (63,1)
Cadillac STS Owner Manual - 2011
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.
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 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: Modifications 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.
Modifications 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 6 ‑ 4 .
This light comes on during a malfunction in one of
two ways:
Light Flashing: A misfire condition has been detected.
A misfire 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.
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