2007 Chevrolet Tahoe Owner's Manual - Page 254

Notice: If you keep driving your vehicle with this light on, after awhile, 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: Modifications 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. Modifications 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. See Accessories and Modifications on page 444. This light should come on, as a check to show you it is working, when the ignition is on and the engine is not running. If the light does not come on, have it repaired. This light will also come on during a malfunction in one of two ways: • Light Flashing - A misfire condition has been detected. A misfire increases vehicle emissions and may damage the emission control system on your vehicle. Diagnosis and service may be required. • Light On Steady - An emission control system malfunction has been detected on your vehicle. Diagnosis and service may be required. If the Light is Flashing The following may prevent more serious damage to your vehicle: • Reducing vehicle speed • Avoiding hard accelerations • Avoiding steep uphill grades • If you are towing a trailer, reduce the amount of cargo being hauled as soon as it is possible If the light stops flashing and remains on steady, see "If the Light Is On Steady" following. 254