Why would the emission control system light be on in an Audi a3 2.0 FSI?

The emission control system light in an Audi A3 2.0 FSI may turn on due to various issues, such as a faulty oxygen sensor, a malfunctioning catalytic converter, or a leak in the exhaust system. It could also indicate problems with the engine's fuel system or issues with the onboard diagnostics. Immediate attention is recommended, as ignoring the light could lead to decreased performance or increased emissions. A diagnostic scan can help identify the specific issue triggering the warning.