I just became a proud owner of a used 2002 bmw 318i se i was told by the seller he did DIY with the oil service just before he put it up for sale, though the service indicator is still showing over -6000. I tried to reset it, from the cluster, but it isn't responding. is it possible he lied about servicing the car? or perhaps one can only reset the indicator after one may have changed the oil? whats your take?