I have a 2001 S60 2.4T with 159,403 on her. The check engine light has been on about a week. Now when I start the car to the right of the check engine light there is a service light that is lit but goes out when I drive the car. I do not have any warnings in the information panel. What does this light mean and why doesn't the information panel say anything. On my last oil change they read the code saying the check engine light had something to do with the oil sensor so they reset it and now it is back on.Thanks to all who answer.