How to troubleshoot engine warning lights in an Audi A4?

I recently got an engine warning light in my Audi A4 and I'm not sure what to do. Can anyone provide some guidance on how to troubleshoot this issue?

The first step in troubleshooting engine warning lights in an Audi A4 is to check the OBD-II codes using a diagnostic tool. This will give you an idea of what the issue could be. From there, you can either try to fix it yourself or take it to a mechanic for further diagnosis.

Another common issue that can trigger an engine warning light in an Audi A4 is a faulty oxygen sensor. If this is the case, it's best to replace the sensor as soon as possible to avoid any further damage to the engine.

In some cases, a loose gas cap can also cause the engine warning light to come on in an Audi A4. Make sure to check and tighten your gas cap before jumping to more complex troubleshooting steps.