Mercedes-Benz B-Class Service A and B Reset, W246

Last updated: October 24, 2026

Instructions on how to Reset the Service Reminder on the Mercedes-Benz B-Class

What the reset does, and what it does not

Worth being clear about, since this page exists to clear the message: confirming the service in the menu tells the car the work was done. It does not do the work. That sounds obvious written down, but the reminder going away feels like a job finished, and it is not.

It matters more on these cars than on most, because ASSYST PLUS is not a fixed mileage counter. It watches how the car is actually used, so short trips, long idling and hard running all shorten the interval it asks for, and gentle highway miles lengthen it. That also means the car keeps its own record of what was confirmed and at what mileage. A dealer can read that history, and so can anyone inspecting the car later, which is why confirming a full service that was never carried out leaves a permanent gap in the record rather than just silencing a light.

So if you are resetting this after doing the work yourself, make a note of the date, the mileage and what you actually replaced, and keep the receipts for the parts. The car will record that a full service happened. Your note is the only thing that says what that service consisted of, and it is what a buyer will want to see.

Service A and Service B are not the same thing

The two alternate, with A being the lighter visit and B the more extensive one. Exactly what each includes depends on the model, the year and the market, so the honest answer is to check the schedule for your own car rather than trusting a generic list. The reset procedure above is the same either way, since you are confirming whichever service the car is currently asking for.

Reset Service Reminder A / B on Mercedes B-Class