Black plate (20,1)Cadillac CTS Owner Manual (GMNA-Localizing-Europe-8087685) - 2015 -crc - 8/13/145-20 Instruments and Controlsof the vehicle to ensure emissionsare at acceptable levels, helping tomaintain a clean environment. Themalfunction indicator lamp comeson when the vehicle is placed inService Only Mode, as a check toshow it is working. If it does not,have the vehicle serviced by yourdealer. See Ignition Positions onpage 9-13.If the malfunction indicator lampcomes on while the engine isrunning, this indicates that there isan OBD II problem and diagnosisand service might be required.Malfunctions often are indicated bythe system before any problem isapparent. Being aware of the lightcan prevent more serious damageto the vehicle. This system alsoassists the service technician incorrectly diagnosing anymalfunction.{ CautionIf the vehicle is continually drivenwith this light on, the emissioncontrols might not work as well,the vehicle fuel economy mightnot be as good, and the enginemight not run as smoothly. Thiscould lead to costly repairs thatmight not be covered by thevehicle warranty.{ CautionModifications made to the engine,transmission, exhaust, intake,or fuel system of the vehicle orthe replacement of the originaltyres with other than those of thesame Tyre Performance Criteria(Continued)Caution (Continued)(TPC) can affect the vehicle'semission controls and can causethis light to come on.Modifications to these systemscould lead to costly repairs notcovered by the vehicle warranty.This could also result in a failureto pass a required EmissionInspection/Maintenance test. SeeAccessories and Modifications onpage 10-2.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.
