1997 Chevrolet Blazer Owner's Manual - Page 134

Malfunction Indicator Lamp (Service Engine Soon Light) NOTICE: If you keep driving your vehicle withthis light on, after a while, your emission controls may not work as well, your fuel economy may not be as good and yourengine may not run as smoothly. This could lead to costly repairs that may not be covered by your warranty. 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 doesn't comeon, have it repaired. This light will also come on during a malfunction in one of two ways: 0 1 SERVICE ENGINE SOON Your vehicle is equipped with a computer which monitors operation of the fuel, ignition andemission control systems. This system is called OBD I1 (On-Board Diagnostics-Second Generation) and is intended to assure that emissions are at acceptable levels for the life of the vehicle. helping to produce a cleaner environment. ( I n Canada. OBD 11 is replaced by Enhanced Diqnohtics. The SERVICE ENGINE SOON light co111eson t o indicate that there is a problem and service is rquired. X,l;df'unctions often will be indicated by the system bciore a n y problem is apparent. This may prevent mort' serious damage to your vehicle. This system is also t1csignt.d t o assist your service technician in correctly diagnosing any malfunction. Light Flashing -- A misfire condition has been detected. A misfire increases vehicle emissions and may damage the emission control system on your vehicle. Dealer or qualified service center diagnosis and service is required. Light On Steady -- An emission control system malfunction has been detected on your vehicle. Dealer or qualified service center diagnosis and service may be required. 0 2-77