Why is the check engine light on in my Audi A4?

My 2015 Audi A4's check engine light recently came on and I'm not sure what could be causing it. Any advice on how to troubleshoot this issue?

One of the most common reasons for the check engine light to come on in an Audi A4 is an issue with the fuel system. It could be something as simple as a loose gas cap or a more serious issue with the fuel injectors. I would recommend checking the gas cap first and if that doesn't solve the issue, it's best to take it to a mechanic for further diagnostics.

Another common culprit for the check engine light in an Audi A4 is a faulty oxygen sensor. This sensor monitors the amount of oxygen in the exhaust and helps regulate the engine's fuel-to-air ratio. A malfunctioning sensor can lead to decreased fuel efficiency and potentially more serious issues down the line. I suggest taking your car to a certified Audi technician to have the sensor checked and replaced if necessary.

In some cases, the check engine light can be triggered by a loose or damaged wire in the electrical system. This could happen from something as simple as a bump in the road. I would suggest checking all the visible wires and connectors under the hood to make sure everything is secure. If the light persists, it's best to have a professional inspect the car.