General Information

The "Active Service System" (ASSYST) (also known as FSS - Flexible Service System) provides the driver information on service and maintenance due.
The ASSYST is an engine oil maintenance system based on actual requirements. This means that in addition to the pure time and mileage criteria various factors are taken into consideration in determining the actual inspection intervals required. These include quality factors coded with the Hand Held Tester (HHT) as well as other evaluation factors which take the type of operation and therefore actual wear and deterioration into consideration.





After dropping below a warning limit, on vehicles with multi-function display (shown), the remaining mileage or remaining time appears in the text field (b) and the tool symbol (a) is shown in the display. On vehicles without multi-function display they (remaining mileage/time and tool symbol) are shown in the odometer display field (not shown).





Moreover the ASSYST may also have a filling level indicator* for the engine oil. If the oil level is too low or too high it is indicated in the text field (b) and the oil can symbol (a) appears in the display on vehicles with multi-function display (shown).
The complexity of the ASSYST makes it necessary for it to be equipped with its own processor in the instrument cluster.
ASSYST obtains the time information from the electronic clock integrated into the instrument cluster.
The other data required is received via the CAN data bus from the traction system control module and engine control module.

*Some models