There are many differences between the Mercedes-Benz Full A and Full B service packages, including the type of work that is performed during the service and how long the service takes. All Mercedes-Benz vehicles produced in or after 2009 use a Flexible Service System where indicators on the control panel inform the owner when it is time for an A or B service.
The A Service is normally recommended after the vehicle's first 10,000 miles or one year, while the B Service light normally comes on after 20,000 miles or one year. The two service levels alternate, meaning a customer first brings the vehicle in for the A Service, followed by the B Service and then another A Service when the control panel indicates it is time. When it is time for an A Service, the control panel shows one wrench icon, while two wrench icons indicates that it is time for a B Service.
Both the A and B Services include replacing the motor oil and oil filter, checking all fluid levels and connections, inflating and checking the tires and inspecting the brake components. During the service, the mechanic must also reset the maintenance counter so that the vehicle stays on the proper maintenance schedule. In addition to the work performed in the A Service, the B Service also includes changing the cabin dust filter and replacing the brake fluid.