One of the most essential parts of a car that needs to be operating properly is the check engine light. The onboard diagnostic system of the car warns the driver of a potential issue. Even though your car appears to be running smoothly, when the check engine light illuminates, it indicates that one of your car's systems, such as the fuel injection, ignition, or emission control, is not functioning properly. If the catalytic converter is at risk of being harmed, the check engine light should be checked out right away if it comes on and is flashing.   Avoid going too fast when you see a flashing light, particularly if you're towing. There's no need to freak out when the check engine light turns on; simply schedule an appointment to have your car looked at right away. Ignoring your check engine light could result in serious damage to engine parts and increased costs.