Can the check engine light come on automatically?

Yes, the "Check Engine Light" can illuminate automatically for several reasons. Modern vehicles are equipped with Engine Control Units (ECUs) that monitor and regulate critical engine functions. When the ECU detects any abnormalities or faults in the vehicle's sensors or components that control emissions or engine performance, it automatically triggers the Check Engine Light to illuminate on the dashboard. This serves as a warning signal to the driver, indicating the potential need for diagnostics, repairs, or maintenance to address the underlying issues.