GF00.20-D-2007H Remaining Distance, Function
GF00.20-D-2007H Remaining Distance, Function
General
Based on the starting distance, the Active Service System (ASSYST), which is integrated in the instrument cluster (A1), determines the current remaining distance to the next service scope as the service interval, taking into consideration the driving conditions and an engine oil refill detection, with code (JW6) Maintenance computer (ASSYST), on the basis of a bonus and penalty principle.
The remaining distance function consists of the following subfunctions:
- Starting distance
- Bonus and penalty principle for driving conditions
- Bonus principle for engine oil refill detection, with code JW6) Maintenance computer (ASSYST)
- Remaining distance
- Warning threshold (in kilometers)
Starting distance
The starting distance refers to the minimum distance in kilometers which can be driven until the next service. However, this only applies if the prescribed nominal quantity of engine oil was added during a service.
The starting distance is stored in the engine data record for the respective engines below and can be influenced by selecting the engine oil quality in the instrument cluster:
- Engine 642, engine 646 or engine 651:
- 30,000 km, with quality factor of engine oil quality 229.31
- 40,000 km, with quality factor of engine oil quality 228.51
- Engine 271 or engine 272:
- 23,000 km, with quality factor of engine oil quality 229.3
- 30,000 km, with quality factor of engine oil quality 229.5
The starting distance is automatically reset to its start value following every service when the service scope is reset at the instrument cluster.
The starting distance is an internal operand and cannot be shown on the display (A1p1) of the instrument cluster.
The starting distance can only be displayed with STAR DIAGNOSIS. The instrument cluster display shows the remaining distance.
Bonus and penalty principle for driving conditions
The driving conditions are the following data which are recorded in driving mode:
- Travel distance
- Load torque
- Rpm
- Engine oil level
- Engine oil temperature
- Coolant temperature
The data for calculating the travel distance is received by the instrument cluster by way of the Controller Area Network bus class C (engine compartment) (CAN C) from the ESP control unit (N30/4).
The instrument cluster receives the remaining data from the following control units via CAN C:
- CDI control unit (N3/20), with engine 642
- CDI control unit (N3/21), with engine 646
- CDI control unit (N3/28), with engine 651
- ME-SFI [ME] control unit (N3/29), with engine 271
- ME-SFI [ME] control unit (N3/23), with engine 272
An assessment is made based on this data, which is broken down as follows:
- Optimal driving conditions:
- Few cold starts
- No high engine speeds
- Few short-distance trips
- Few trips with a trailer
- Unfavorable driving conditions:
- Many cold starts
- High engine speeds
- Many short-distance trips
- Many trips with a trailer
Optimal driving conditions
A bonus is issued for optimal driving conditions. In this case, a value of at least 0.6 km is applied for one kilometer driven. In other words, only 0.6 km is calculated for one kilometer driven (bonus ≤ 0.4 km).
Unfavorable driving conditions
With unfavorable driving conditions a penalty is issued instead of a bonus. In this case, a value of 1 km is applied for each kilometer driven. In other words, 1 km is calculated for one kilometer driven (bonus/penalty = 0 km).
For vehicles with engine 646 and with code (MF4) Low- emission engine as per EU4 Group 3 a penalty is issued for unfavorable driving conditions (many short-distance trips and low load torque).
In this case, a value of at most 5 km is applied for each kilometer driven. In other words, a maximum of 5 km is calculated for one kilometer driven (penalty ≤ 5 km).
The penalty for unfavorable driving conditions is issued to protect the engine. The fuel content in the engine oil increases under these conditions because the diesel particulate filter (DPF) regeneration operations are stopped when the engine does not reach operating temperature.
Bonus principle for engine oil refill detection, with code (JW6) Maintenance computer (ASSYST)
Replenishment of the engine oil is detected by the following engine oil sensors:
- Engine oil sensor (B40), with engine 642
- Engine oil sensor (B40/5), with engine 646
- Engine oil level sensor (B40/6), with engine 651
With engine 271 or with engine 272 engine oil refill detection is not possible, as these engines only have the following components installed:
- Oil level switch (S43/3), with engine 271
- Oil level switch (S43), with engine 272
- Oil pressure sensor (B40/2), with engine 272 up to 03/07
The data from the listed engine oil sensors is read in by the CDI control unit and sent over CAN C to the instrument cluster.
A one-off bonus is issued for every engine oil refill detected, which is added to the remaining distance.
The size of the bonus varies and depends on the following factors:
- Amount of engine oil replenished
- Current engine oil quality
- Current driving conditions
As there is no fixed amount for an engine oil refill and as the current values for the engine oil quality and the driving conditions are used in the calculation, it is only possible to provide information about the value of the bonus by means of a characteristic curve.
Remaining distance
Immediately after resetting the service scope, the remaining distance is equivalent to the starting distance, if during the service the prescribed nominal engine oil quantity was added.
The remaining distance is the distance remaining between the current kilometer reading and the next service.
The remaining distance can also be extended or shortened based on the bonus and penalty principles outlined above.
This provides the remaining distances listed below for the particular engine as a function of the starting distance:
Engine 271 with a starting distance of 30,000 km, with a quality factor of engine oil quality 229.3/31 229.5/51: and
- Minimum remaining distance = 30,000 km
- Maximum remaining distance = 30,000 km
Engine 272 with a starting distance of 23,000 km, with a quality factor of engine oil quality 229.3:
- Minimum remaining distance = 23,000 km
- Maximum remaining distance = 38,000 km
Engine 272 with a starting distance of 30,000 km, with a quality factor of engine oil quality 229.5:
- Minimum remaining distance = 30,000 km
- Maximum remaining distance = 40,000 km
Engine 642 with a starting distance of 30,000 km, with a quality factor of engine oil quality 229.31:
- Minimum remaining distance = 20,000 km
- Maximum remaining distance = 50,000 km
Engine 642 with a starting distance of 40,000 km, with a quality factor of engine oil quality 228.51:
- Minimum remaining distance = 20,000 km
- Maximum remaining distance = 50,000 km
Engine 646 engine 651 and with a starting distance of 30,000 km, with a quality factor of engine oil quality 229.31:
- Minimum remaining distance = 5000 km
- Maximum remaining distance = 50,000 km
Engine 646 engine 651 and with a starting distance of 40,000 km, with a quality factor of engine oil quality 228.51:
- Minimum remaining distance = 5000 km
- Maximum remaining distance = 50,000 km
The remaining distance appears in the instrument cluster display as standard.
However, for drivers of vehicles with low annual mileage, the vehicle's operation time is always being processed in the background, to ensure the drivers are informed of an upcoming service interval. The remaining distance is compared with the remaining time on a daily basis. Under certain conditions, the display on the instrument cluster changes and shows the remaining time.
If ASSYST, which is integrated in the instrument cluster, lacks the measured values, e.g. due to the failure of the engine oil sensor or the engine oil level sensor, then the substitute values stored in the CDI control unit are used.
A corresponding fault entry is made to the fault memory of the following components:
- Instrument cluster
- CDI control unit
- ME-SFI [ME] control unit
If the operating voltage fails, the data are retained.
Warning threshold (in kilometers)
The warning threshold is 3000 km before the end of the remaining distance.
