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Active Service System (ASSYST) function - GF00.20-P-0003R: Notes

MODEL 230 

General 

With the "Active Service System" (ASSYST)  , the driver's attention is drawn to a service which is due. In addition, the necessary scope of the service is determined and displayed. ASSYST is an engine oil maintenance system that monitors engine oil requirements  . This means that, in addition to a pure time and distance criterion, various factors are taken into consideration in order to calculate the service intervals.

On the one hand, this includes quality factors  , which are coded with Star diagnosis and, on the other hand, evaluation factors  , which take driving conditions, and therefore actual wear, into consideration.

The service interval in the case of favorable evaluation (few cold starts, driving predominantly in the mean speed range) is longer than in the case of unfavorable evaluation.

Display 

Display is carried out with the multifunction display on the left (A1p13) and right (A1p15) of the instrument cluster (A1).

The service interval is displayed when requested by the driver or, in the event of negative deviation from a warning threshold  , automatically as a remaining distance  or remaining time  in the text field (3) of the right multifunction display (A1p15). The service symbol additionally appears in the left multifunction display (A1p13) (Figure 1).

Engine oil monitoring 

In the event of a low oil level or overfilling, information regarding the oil level is blended into the text field (3) in the right multifunction display (A1p15) (Figure 2). The oil can symbol additionally appears in the left multifunction display (A1p13).

Oil top-ups can additionally be detected by the system. If oil is topped up, a quantity rebate, which may extend the service interval, is assigned.

Depending on evaluation and quantity rebate, the service interval is 15, 000 to 30, 000 kilometers, or 10, 000 to 20, 000 miles.

Technology and variables 

In order to determine the monitored service interval, ASSYST requires the values of various variables. These serve to calculate the service interval.

In addition to the evaluation factors  , which depend on the real-life driving conditions, quality factors  are also used to determine the monitored service interval (remaining distance and remaining time).

Influencing variables 

The instrument cluster (A1) receives this information via the engine compartment CAN from the fuel injection system control module (N3).

For the oil level, engine oil temperature and oil correction factor data, the ME-SFI control module (N3/10) reads in the data from the oil sensor (oil level, temperature and quality B40)  .

Example of service display 

Fig 1: Identifying Service Symbol And Label
G05075153Courtesy of MERCEDES-BENZ USA

IMPORTANT Further displays can be found in other documents, especially in the document: "Active Service System (ASSYST) Mercedes-Benz Driver Information Service".

Example of engine oil display 

IMPORTANT Further displays can be found in other documents especially in the document: "Active Service System (ASSYST) Mercedes-Benz Driver Information Service".

Fig 2: Identifying Oil Can Symbol And Label
G05075154Courtesy of MERCEDES-BENZ USA

IMPORTANTDiagnosis 

ASSYST diagnosis is carried out with Star diagnosis  . In this case, access is achieved via the instrument cluster (A1)  . During diagnosis, the control module for fuel injection systems (N3) must also be taken into consideration.

IMPORTANTInadvertently activated oil change reset 

If an oil change reset has been activated on the instrument cluster (A1) or with the star diagnostic tool, but no  oil change has to be carried out, this oil change reset must be immediately reset. A corresponding menu is available in Star diagnosis for this purpose.

IMPORTANTReplacement of the instrument cluster (A1) 

If the instrument cluster (A1) has to be replaced, the codes and data records must be transferred into the new instrument cluster. See the menu assistance in Star diagnosis.

IMPORTANTReplacement of the oil sensor (oil level, temperature and quality B40) 

In the event of complaint following the replacement of the oil sensor (oil level, temperature and quality B40)  the minimum oil level warning may possibly have to be adjusted (calibrated). This must always be carried out if the message "CHECK ENGINE OIL LEVEL!" appears, but the oil level is still OK according to the oil dipstick. Adjustment is carried out via menu assistance with Star diagnosis.

  Active Service System (ASSYST) component networking   GF00.20-P-0003-07R 
  Display service function   GF00.20-P-2010R 
  Remaining distance function IMPORTANT Also contains information regarding the startup distance  . GF00.20-P-2007R 
  Remaining time function IMPORTANT Also contains information regarding the startup time  . GF00.20-P-2008R 
  Engine oil monitoring function   GF00.20-P-2009R 
  Oil sensor location/task/design/function   GF18.40-P-4111A
  Active Service System (ASSYST) operating instructions   GF00.20-P-0003-01R 
  Active Service System (ASSYST) Mercedes- Benz Driver Information Service   GF00.20-P-0003-02R 
  Table of contents, function description, instrument cluster   GF54.30-P-0997R