Front Multicontour Seat (MKS), Function - GF91.25-P-0005RFM
Model 205 as of model year 2019 with code 409 (Left and right front multicontour seat)
Function requirements, general
- Terminal 15 ON
- No on-board electrical system limp-home mode
The electronic ignition lock control unit sends the status of circuit 15 via interior CAN to the multicontour seat pneumatic pump and to the multicontour seat control units.
Function description of multicontour seat, general
The multicontour seat combines the advantages of a comfortable multicontour seat with those of a sport seat. The contour and surface hardness of the backrest of the driver and front passenger seat can be changed individually. This is done by air cushions that can be inflated independently of each other. The lateral support in the driver and front passenger seat is made possible by a basic pressure in the lateral support air cushions.
The multicontour seat is also equipped with a massage function in order to prevent tension during long journeys.
Model 205 as of model year 2019 with code 299 (PRE-SAFE) with code 409 (Left and right front multicontour seat)
In critical situations, the seat contour of the driver or front passenger seat is automatically changed to achieve a favorable seat position and secure the vehicle occupant.
The multicontour seat function comprises the following subfunctions:
- Function sequence for setting the air cushion pressure
- Function sequence for the massage function
Function sequence for setting the air cushion pressure
The contours and the surface hardness of the backrest can be adjusted individually on the multicontour seat by inflating and deflating the air cushions.
The air cushions are arranged as follows:
- In the seat side bolsters of the backrest on the left and right
- In the upper lumbar area
- In the lower lumbar support area
Inflation and deflation are controlled via a menu in the head unit.
The head unit sends the adjustment requests via user interface CAN, electronic ignition lock control unit and interior CAN to the respective front multicontour seat control unit. The respective multicontour seat control unit with the aid of the multicontour seat pneumatic pump supply the air required to inflate the air cushions.
Model 205 as of model year 2019 with code 242 (Front passenger seat, electrically adjustable with memory function) with code 409 (Left and right front multicontour seat)
Model 205 as of model year 2019 with code 275 (Memory Package (driver's seat, steering column and mirror)) with code 409 (Left and right front multicontour seat)
The adjustments of the driver or front passenger seat can be stored and called up again using the memory function of the electrical seat adjustment.
Short-term and long-term control:
The short-term control compensates for overpressure deviations in the air cushions. It activates following every adjustment procedure and only remains active for a short parameterizable period of time. This function is used among others to compensate for sitting down or leaning back immediately and in a comfort-oriented fashion. After the short-term control, the long-term control becomes active. Here, the pressure supply is regulated such that the specified pressure is always achieved. This is done almost without the driver or front passenger noticing.
An adjustment is aborted under the following conditions:
- Overvoltage or undervoltage
- Inflating or deflating timeout
- Leak in one or more air cushions
Function sequence for the massage function
The massage function is a comfort function and helps the driver or front passenger to relax, particularly during longer trips. For the realization of the massage programs, the air cushions in the upper and lower lumbar area are actuated so that a pulsation is achieved in the lumbar area of the seat backrest.
The massage function is operated via a menu in the head unit.
Model 205 as of model year 2019 with code 409 (Left and right front multicontour seat) with code 531 (COMAND APS)
The massage function can be operated via the voice control system of the head unit.
The following massage programs can be selected:
- "Undulating massage"
- "Pulsating massage"
The head unit sends the "Massage function ON" request via user interface CAN, electronic ignition lock control unit and interior CAN to the respective multicontour seat control unit. The respective multicontour seat control unit regulates the air supply required to fill the air cushions by actuating the respective multicontour seat pneumatic pump.
The massage function is interrupted for the following adjustments:
- Manual adjustment of air cushions
- Memory adjustment request
After the interruption, the massage starts in its sequential control system with the next upcoming massage step.
The massage function is canceled under the following conditions:
- Overvoltage or undervoltage
- Overloading of the multicontour seat pneumatic pump
- Adjustment request from PRE-SAFE® (with code 299 (PRE-SAFE® system))
| Electrical function schematic for front multicontour seat (MKS) | PE91.25-P-2053-97FBA | ||
| Overview of system components for electric seats | GF91.29-P-9992RF |