GF00.20-P-0004TA Active Service System (ASSYST Plus), Function

GF00.20-P-0004TA Active Service System (ASSYST PLUS), Function
- MODEL 211 with ENGINE 642
- MODEL 211 with ENGINE 271 as of 1.6.05
- MODEL 211 with ENGINE 272

General information
Calculation of the service date is determined by the ASSYST system. Additional maintenance items are handled by the ASSYST PLUS system.
ASSYST PLUS determines, from measured values or variables determined there from as well as from data stored in its read-only memory, the next service date due for the vehicle in question. Both distance-related and time-related variables are taken into account. ASSYST PLUS can be configured, enabling it to be adapted to various vehicle uses. This is implemented in the central gateway control unit (N93).

The central gateway control unit (N93) is connected to the vehicle control units via the Controller Area Network bus, Class B (interior) (CAN B) and Controller Area Network bus, Class C (engine compartment) (CAN C).
During configuration of the maintenance algorithm, it is determined whether the required data is acquired solely by the system or whether it is taken from other modules, such as the ASSYST. ASSYST only takes into account the oil change intervals; ASSYST PLUS covers all vehicle maintenance requirements.

ASSYST PLUS is implemented as a module in parallel with ASSYST.

Operation during the vehicle's first 250 km
ASSYST PLUS is linked primarily to the Controller Area Network (data bus/CAN bus) (CAN) messages provided by the instrument cluster (A1). For the instrument cluster (A1) it is possible to reset the main odometer within the first 250 km of vehicle operation. An instrument cluster (A1) reset is no longer possible after the 250 km limit has been reached.
ASSYST PLUS does not perform any maintenance item calculations until this distance has been reached. However, upon reaching the main odometer, the traveled distance of 250 km is once taken into consideration in calculating and evaluating the maintenance items. This main odometer threshold is not taken into consideration again by ASSYST PLUS.

The following modules are integrated into the central gateway control unit (N93):
- System diagnosis
- ASSYST
- ASSYST PLUS
- Target date for exhaust emissions inspection (AU) and main inspection (HU)

Data analysis
Single or a number of stored service items with their intervals can be assigned to the basic items.
All service events are stored in the history memory and can be read out at any time via STAR DIAGNOSIS.
The service calculation module calculates an optimum service scope from the data from all the integrated modules using an internal computation.
This service scope takes the model designation, the date, the mileage, service-related special equipment and retrofitted installations into consideration.
If the service date has been reached, the service indicator in the instrument cluster (A1) is activated automatically via ASSYST PLUS.

Display
The displays are shown in the multifunction display (A1p13) of the instrument cluster (A1). The following instructions can be displayed with service codes:
- Service X in.....days
- Service X in.....km
- Carry out Service X

A "+" after the service indicator identifies the degree of wear of the brake linings. The brake lining thickness must be checked on the service date.
The service date is displayed at least 1000 km or 30 days before the next service is due. The service display consists of the term "Service" followed by the specific service code.
The service code includes the time taken and is classified from A to H:
- Code A: Service scope of up to 1 h
- Code B: Service scope of up to 2 h
- Code H: Service scope of up to 8 h

The service interval can be displayed on driver request or upon exceeding a warning threshold automatically as the remaining distance in the multifunction display (A1p13).

Technology and influencing factors
ASSYST PLUS needs the values of various influential parameters to calculate the requirement-based service interval.
In addition to the evaluation factors, which depend on the real-life driving conditions, quality factors may also be used to determine the monitored service interval (remaining distance and remaining time). Various readings listed below are required for data capture.

The following data from the CAN-B is required:
- Terminal status, circuit 15
- Vehicle speed
- Total odometer reading (km)
- Day cycle counter
- Date
- Terminal status, circuit 61

The following data from the CAN-C is required:
- Pedal value
- Engine speed
- Cylinder shutoff
- Engine torque, static
- Engine torque, maximum
- Engine torque, minimum
- Engine temperature
- Engine off time
- Vehicle lateral acceleration

ASSYST PLUS diagnosis is performed using STAR DIAGNOSIS. Entry is accomplished via the central gateway control unit (N93), which is connected to the data link connector (X11/4).

In addition to calculating the next service date, the indication for the next main vehicle inspection date and the emissions inspection date are calculated and displayed in the multifunction display (A1p13) using ASSYST PLUS in the central gateway control unit (N93).

Before the instrument cluster (A1) can be replaced, the trip odometer must be read out. Following this, the instrument cluster (A1) to be replaced can be replaced with a new one.

Before learning in, the key ID on the instrument cluster (A1) it is necessary for the trip odometer readout to be written to the new instrument cluster (A1). Only then, it is possible to perform the learning operation for the key ID.

In the event of a malfunction in the instrument cluster (A1) or in the EZS control unit (N73) service data is no longer transferred and is kept at the last current status.

If service was confirmed on the instrument cluster (A1) or with STAR DIAGNOSIS even though no service was performed, this service confirmation must be reset immediately. Only the last confirmation can be reset.