I do my own oil changes at a friend's shop in between the dealer's annual low mileage oil change. Everytime I do an oil change the due date for the next oil service automatically moves ahead one year, can't remember if the mileage resets on its own but I'm certain about the date.
This has actually thrown off my dealership when I bring the car in for its annual oil service because the car is showing a date one year away. For example, my car normally has an annual cycle that falls on September. It should show September 2012 and it did show September 2012 after the dealership completed an oil change in September of 2011. When I completed one myself mid-year the date moved forward to September of 2013.
Somehow the CBS knows that an oil change has been done and automatically moves the date forward.
Has anyone else come across this and is there a way to prevent the date from moving forward automatically when doing your own oil changes in between the dealer oil change?