1998 Buick Century Owner's Manual - Page 136

This system is called OBD (On-Board I1 Diagnostics-Second Generation) and is intendedto assure for that emissions are at acceptable levels the life of the vehicle, helping to produce a cleaner environment. The SERVICE ENGINESOON light comes on and a chime will sound to indicate that there is a problem service is and required. Malfunctions often will be indicated the by This may prevent system before any problem is apparent. more serious damageto your vehicle. This system is also designed to assist your service technicianin correctly diagnosing any malfunction. 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 come on, have it repaired. This lightwill 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. Dealer or qualifiedservice center diagnosis and service may be 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. NOTICE: If you keep driving your vehicle with this light on, aftera while, your emission controls may not work as well, your fuel economy may not be as good and your engine may run as smoothly. not This could lead to costly repairs that may not be covered by your warranty. 2-60