its a dumby light that comes on at certain intervals so you bring your car into the dealership so they can tell you all kinds of nonsense to get done on your car. the only thing that triggers it to come on is mileage.
turn your car off, hold the "reset" button on your dash in, count to 15....turn your car to "on" (dont start it) while still holding in "reset", keep holding it till the light goes off and youre set.
when it just blinks, then goes away, its just means that a maintenance interval is coming up. once it stays on, youre either at, or passed that interval.