An illuminated check engine light indicates a potential issue within a vehicle’s emissions system, or other critical components monitored by the onboard diagnostic system. This signal can range from minor concerns, such as a loose gas cap, to more severe problems like a malfunctioning catalytic converter. A diagnostic trouble code (DTC) is stored in the vehicle’s computer, providing specific information about the triggered warning.
Prompt attention to this warning is crucial for vehicle longevity and driver safety. Ignoring the light can lead to worsening mechanical problems, decreased fuel efficiency, potential damage to expensive components, and even hazardous driving conditions. Early diagnosis allows for timely repairs, preventing minor issues from escalating into costly major repairs. Modern onboard diagnostic systems offer a significant advancement over older vehicles, enabling mechanics to quickly and accurately pinpoint problems, saving time and resources.