Most new cars eliminate the guesswork of when your next oil change is due, as most now have a reminder system that displays a "Change Oil" message right where the driver can see it. The 2006 Mercedes C280 has this feature, and resetting this maintenance reminder system isn’t too difficult.
Resetting Maintenance Reminder System
Enter the car, close the door and turn the ignition to position "2." Press and release the up or down arrows on the steering wheel until the wrench icon shows on the instrument panel display. Press and hold the trip reset button — the small button to the left of the instrument panel — until the instrument panel display reads "Service interval to reset, press reset button for 3 sec." Press and hold the trip reset button until you hear the beep and the display reads "Service interval has been reset." Turn the key off.