I can predict one thing...you probably won't make it out of the dealer for under $500 unless it is under warranty, regardless of what is wrong. You didn't say if you bought it from a dealer or private seller but if from the dealer then they should resolve it for free if it is within a couple of weeks of purchase.

I'm sure that you can safely drive the car if there are no "symptoms" so to run to the dealer with some sense of urgency for a CEL is silly IMHO.

Buy a scanner, scan it and in less time than you will spend at the service advisor's counter you will know what is wrong. Any OBDII scanner should do but just ask at the parts store what they recommend. You can spend a lot on one but they all basically do what you need - read codes and reset them.

__________________
Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz