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Malfunction Indicator Lamp: Description and Operation

SERVICE ENGINE SOON LIGHT
The Service Engine Soon light comes on to indicate that there is a problem and service is required. This light does NOT come on at certain mileage intervals. Malfunctions often will be indicated by the system before any problem is apparent. This may prevent more serious damage to your vehicle. This system is also designed to assist the service technician in correctly diagnosing any malfunction.