Black plate (21,1)Cadillac CTS/CTS-V Owner Manual (Include Mex) - 2012Instruments and Controls 5-21This light should come on when theignition is on, but the engine is notrunning, as a check to show it isworking. If it does not, have thevehicle serviced by your dealer.If the malfunction indicator lampcomes on and stays on while theengine is running, this indicates thatthere is an OBD II problem andservice is required.Malfunctions often are indicated bythe system before any problem isapparent. Being aware of the lightcan prevent more serious damageto the vehicle. This system assiststhe dealer technician in correctlydiagnosing any malfunction.Notice: If the vehicle iscontinually driven with this lighton, the emission controls mightnot work as well, the vehicle fueleconomy might not be as good,and the engine might not run assmoothly. This could lead tocostly repairs that might not becovered by the vehicle warranty.Notice: Modifications made tothe engine, transmission,exhaust, intake, or fuel systemof the vehicle or the replacementof the original tires with otherthan those of the same TirePerformance Criteria (TPC) canaffect the vehicle's emissioncontrols and can cause this lightto come on. Modifications tothese systems could lead tocostly repairs not covered by thevehicle warranty. This couldalso result in a failure topass a required EmissionInspection/Maintenance test.See Accessories andModifications on page 103.This light comes on during amalfunction in one of two ways:Light Flashing: A misfire conditionhas been detected. A misfireincreases vehicle emissions andcould damage the emission controlsystem on the vehicle. Diagnosisand service might be required.To prevent more serious damage tothe vehicle:. Reduce vehicle speed.. Avoid hard accelerations.. Avoid steep uphill grades.. If towing a trailer, reduce theamount of cargo being hauledas soon as it is possible.
