All services include a full 21 point health check to identify worn/faulty components. Servicing should be done at least annually and should follow this pattern according to BMW – A B A C A B A C etc. Officially the service indicator will tell you to service the car at 15,500 miles. A lot of owners choose to carry out an “A” service below at half that distance (7750 miles) which is more realistic taking the vehicle’s age into account. This would mean the schedule would go A A A B A A A C etc.