What causes the "Check Engine" light to turn on in a Ford Mondeo?

I recently purchased a used Ford Mondeo and noticed that the "Check Engine" light turns on randomly. What could be the possible causes for this and how can I fix it?

The most common reason for the "Check Engine" light to turn on in a Ford Mondeo is a faulty oxygen sensor. It is recommended to get it replaced by a certified mechanic to ensure proper functionality of your car.

Sometimes, a loose gas cap can also trigger the "Check Engine" light. Make sure to tighten it properly and see if the light turns off. If it doesn't, then it might be a different issue and needs to be checked by a professional.

Another common reason for the "Check Engine" light to turn on is a malfunctioning catalytic converter. If you notice a decrease in fuel efficiency or a strange smell coming from the car, then it might be the cause. Get it checked and replaced if necessary.