How do I troubleshoot my Audi A3's check engine light?

My Audi A3's check engine light came on and I'm not sure what to do. Can I fix this myself or do I need to take it to a mechanic? How serious is this issue?

The first step to addressing the check engine light is to check your owner's manual to see if there are any known issues or recalls for your specific model. If not, you can use a code reader to scan the car's computer and see what the specific error code is. This will give you a better idea of the issue and whether it may be an easy fix or something that requires a professional's attention.