What is the CAT warning light for in an A3 Audi?

The CAT warning light in an Audi A3 indicates an issue with the catalytic converter or the vehicle's emissions control system. This light can signify that the catalytic converter is not functioning properly, which may affect the vehicle's performance and increase emissions. It's important to address this warning promptly by having the vehicle inspected to avoid potential damage and ensure compliance with emission regulations.