An illuminated check engine light signals a potential problem within a vehicle’s emissions system, engine performance, or other crucial components. This visual alert, triggered by the vehicle’s onboard diagnostic system (OBD-II), ranges in severity from minor issues like a loose gas cap to significant malfunctions such as catalytic converter failure. A flashing light typically indicates a more serious problem requiring immediate attention.
Understanding the implications of this warning is vital for vehicle maintenance and driver safety. Ignoring it could lead to costly repairs, reduced fuel efficiency, or even catastrophic engine damage. Historically, pre-OBD-II systems offered limited diagnostic capabilities. The standardization of OBD-II in the mid-1990s provided a more sophisticated and universal approach to vehicle diagnostics, empowering drivers and mechanics with more detailed information about potential problems.