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Active service system (ASSYST), function - GF00.20-P-0003D: Notes

Model 208 as of 1.8.99 with ENGINES 112, 113 

Model 210 as of 1.7.99 with ENGINES 112, 113, 611, 612, 613 

Model 203 with ENGINE 111, 112, 113, 271 up to 31.5.05, 611, 612, 646 

General information 

With the Active Service System (ASSYST) the driver's attention is drawn to a service due and the required service scope (A/B). The ASSYST system is a demand-based engine oil service system. In addition to the time and distance criterion, various factors are consequently taken into account for calculating the demand-based service intervals.

These are, on the one hand, quality factors which are coded via STAR DIAGNOSIS and, on the other hand, evaluation factors which take into account driving conditions and thus actual wear and tear.

If the evaluation is favorable (small number of cold starts, driving mainly in the mid rpm range) the service interval is longer than for an unfavorable evaluation.

Display 

The displays are shown in the multifunction display (A1p13) of the instrument cluster (A1). The service interval is shown automatically as remaining distance or remaining time in the text fields together with the service symbol upon request of the driver or if a warning threshold is undershot.

Engine oil monitoring 

If there is a shortage or an overfilling of oil, information regarding the oil level appears in the text fields of the multifunction display (A1p13). The oil can symbol also appears. In addition, it is possible to detect oil replenishments. If oil is replenished, a bonus is issued which may extend the service interval. Depending on the assessment the service interval for gasoline engines is 15,000 to 30,000 km or 10,000 to 20,000 miles, for diesel engines it is 20,000 to 40,000 km.

Technology and influencing factors 

In order to determine the demand-based service interval, ASSYST requires the data relating to various influencing variables, which are used for calculating the service interval and the type of service (A or B) required.

In addition to the evaluation factors which depend on real driving conditions, quality factors are also used for determining the demand-based service interval (remaining distance and remaining time).

Influencing variables and evaluation factors 

dependent on real-life driving conditions

The instrument cluster (A1) receives this information over the Controller Area Network bus Class C (engine compartment) (CAN-C) from the vehicle-specific engine control unit.

The vehicle-specific engine control unit reads in the data for oil level, engine oil temperature and oil correction factor from the oil sensor (oil level, temperature and quality) (B40).

Quality factors 

They are factory-set to base values. They can be changed via STAR DIAGNOSIS, if required by the operating conditions. They influence the starting distance:

Time 

The time information is supplied to the ASSYST by a time sensor integrated in the instrument cluster (A1).

Travel distance 

To calculate the travel distance, ASSYST receives the signals of the 4 sensors for wheel speeds over CAN-C from the ESP and BAS control unit (N47-5) (models 203, 208) or ESP, SPS [PML] and BAS control unit (N47-5) (model 210).

IMPORTANT Diagnosis of ASSYST is performed using STAR DIAGNOSIS. Diagnosis is started through the instrument cluster (A1). The engine control units are also included in the diagnosis.

IMPORTANT If an oil change reset is initiated on the instrument cluster (A1) or using the STAR DIAGNOSIS, but an oil change not actually performed, then this oil change reset must be immediately reset. A corresponding menu is available in STAR DIAGNOSIS for this purpose.

IMPORTANT If the instrument cluster (A1) has to be replaced, the codes and data records must be transferred into the new instrument cluster (A1). See menu guidance in STAR DIAGNOSIS.

IMPORTANT In the event of a 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. The menu-assisted diagnosis is performed using STAR DIAGNOSIS.

  Active Service System (ASSYST), block diagram Model 203 GF00.20-P-0003-03PP
    Model 208, 210 GF00.20-P-0003-03S 
  Active service system (ASSYST) Operating instructions, resetting   GF00.20-P-0003-01C 
  Active service system (ASSYST), Mercedes-Benz driver information service Model 203 up to 23.4.04
Display indications
GF00.20-P-0003-02A 
    Model 203 as of 24.4.04
Display indications
GF00.20-P-0003-02P
    Replenishment recognition GF00.20-P-0003-02D 
    Remaining distance information GF00.20-P-0003-02E 
    Remaining time indication GF00.20-P-0003-02F 
  Remaining distance, function   GF00.20-P-2007B 
  Remaining time, function   GF00.20-P-2008B 
  Engine oil monitoring, function   GF00.20-P-2009S 
  Display service scope, function   GF00.20-P-2010A