Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -2016 - crc - 11/6/15Instruments and Controls 133previous guidelines and see yourdealer for service as soon aspossible.If the light is on steady : Amalfunction has been detected.Diagnosis and service may berequired.Check the following:. If fuel has been added to thevehicle using the capless funneladapter, make sure that it hasbeen removed. See “Filling theTank with a Portable Gas Can”under Filling the Tank 0 253.The diagnostic system candetect if the adapter has beenleft installed in the vehicle,allowing fuel to evaporate intothe atmosphere. A few drivingtrips with the adapter removedmay turn off the light.. Poor fuel quality can causeinefficient engine operation andpoor driveability, which may goaway once the engine is warmedup. If this occurs, change thefuel brand. It may require atleast one full tank of the properfuel to turn the light off. SeeFuel 0 251.If the light remains on, see yourdealer.Emissions Inspection andMaintenance ProgramsIf the vehicle requires an EmissionsInspection/Maintenance test, thetest equipment will likely connect tothe vehicle's Data LinkConnector (DLC).The DLC is under the instrumentpanel to the left of the steeringwheel. Connecting devices that arenot used to perform an EmissionsInspection/Maintenance test or toservice the vehicle may affectvehicle operation. See Add-OnElectrical Equipment 0 260. Seeyour dealer if assistance is needed.The vehicle may not passinspection if:. The light is on when the engineis running.. The light does not come onwhen the ignition is in ServiceOnly Mode.. Critical emission control systemshave not been completelydiagnosed. If this happens, thevehicle would not be ready forinspection and might requireseveral days of routine drivingbefore the system is ready forinspection. This can happen ifthe 12-volt battery has recentlybeen replaced or run down, or ifthe vehicle has been recentlyserviced.See your dealer if the vehicle willnot pass or cannot be made readyfor the test.Brake System WarningLightThe vehicle brake system consistsof two hydraulic circuits. If onecircuit is not working, the remaining
