What does the "check engine" light indicate in a vehicle?

The "check engine" light serves as a warning indicator that alerts the driver to a potential issue detected by the vehicle's onboard diagnostics system. Specifically, it signifies that there is a fault in the engine, emissions system, or other related components. When the engine control module identifies a problem, it triggers this alert to prompt the driver to have the vehicle inspected. This is crucial for maintaining the vehicle’s performance, efficiency, and regulatory compliance concerning emissions standards.

In contrast, other indicators like low fuel level, oil change reminders, and brake system malfunctions are typically represented by separate warning lights or messages on the dashboard. These specific alerts are designed to inform the driver about issues directly related to fuel supply, engine oil conditions, or braking system performance, which does not overlap with the broad indication provided by the "check engine" light. Understanding this distinction is key for proper vehicle maintenance and ensuring that any detected problems are addressed promptly to avoid more significant damage or performance issues.