What does a check engine light typically indicate?

The check engine light serves as an important indicator within a vehicle's onboard diagnostics system, signaling that the engine control module (ECM) has detected an issue that could affect the vehicle's performance, emissions, or overall operation. When the light illuminates, it often indicates a malfunction in the engine or associated systems, which may include problems with the ignition system, fuel system, sensors, or emission controls.

This early warning allows drivers and mechanics to address potential issues before they escalate into more serious problems. The onboard diagnostics can provide a fault code that helps in diagnosing the specific issue, guiding effective repairs and maintenance.

While the other options address various aspects of vehicle maintenance, they do not pertain to the specific function of the check engine light. Regular maintenance, low fuel, and oil change requirements are important for vehicle upkeep but are not directly linked to the operational diagnostics indicated by the check engine light.