Reseting the FSS Flexible Service System - PeachParts Mercedes-Benz Forum

Texholdem · #1 01-14-2008, 10:40 AM

I found this article worth reading.

http://www.mercedesmanuals.com/articles.asp?id=123

The content is cut&pasted below lest the link does not work.

Reseting the FSS Flexible Service System
FSS Reset Procedure

If you do an oil change yourself, which most people do you will need to reset the FSS, or Flexible Service System light. This cannot be reset with a scan tool, as those are designed for reading codes in the check engine light, and the below procedure will not work for a check engine light issue.

First How the System works:

The Flexible Service System calculates in both miles and time, how long before you need to service the engines oil. Simply press the mileage button 2 times and you will see this displayed on the dash.

The new V8 & V6 motors are equipped with an oil quality sensor connected to the cars, computer system, as well as an oil level indicator. These two sensors as well as sensors from the cars CAN-BUS system feed additional data such as Speed, Engine and Coolant Temperture, Load Factor, RPM, and Engine Oil Temperature.

Additional factors, such as operating conditions, stop and go driving, high speed driving, cold starts, and oil usage are also calculated to determine the time/distance between oil changes. If your driving conditions are right, the system may even extend the 10,000 mile service intervals. However, oil is not that expensive, and we not recommend attempting to drive that long on one batch of oil. You cannot damage the engine changing the oil too frequently, however, you can certainly burn out rings, seals, and bearing by not changing your oil regularly.

How to Reset the System:

This technique has always worked for me, and is exactly as it was mentioned in my owners manuals under FSS so your mileage may vary:

Your Key Switch has 4 detents or positions.

Position 0 – Locked Wheel – Engine Off
Position 1 – Wheel Unlocked – Engine Off
Position 2 - Wheel Unlocked – Engine On – This is where you normally have the key when driving
Position 3 – Wheel Unlocked – Starter Engaged

Now you are going to use the same button, that when pressed twice, displayed your remaining time and mileage. Normally the R button.

Get in the car and close the doors. Put your finger on the R button but do not press it yet.

Turn your key to the Run (ON) Position, Number 2 from the list.

Now Press the R Button 2 times.

You will see the number of miles or days remaining for service displayed.

Turn the key to the off position within a few seconds.

Press and Hold the R Button while turning the key back to the run position (2).

Nothing has changed yet – do not panic, keep holding in the R button for 10-15 seconds more, you should hear a beep, and now the see that the system has reset the service interval. Let go of the button and you are all set.