GF91.25-P-2023FL Dynamic Lateral Support For Dynamic Multicontour Seat, Function

GF91.25-P-2023FL Dynamic Lateral Support For Dynamic Multicontour Seat, Function
- with CODE (432) Left and right dynamic multicontour seat

Function requirements, general
^ Circuit 15 ON
^ Pressure supply active
^ No on-board electrical system limp-home mode
^ Status of pneumatic pump for dynamic multicontour seat (M40/1) on interior CAN (CAN B) okay
^ High voltage supply in left front dynamic multicontour seat control unit (N32/19) or right front dynamic multicontour seat control unit (N32/22) okay
^ Corresponding driver dynamic multicontour seat button group (S109) or passenger dynamic multicontour seat button group (S108) recognized as inserted
^ v > 10 km/h

Additional function requirements for passenger side
^ Seat assignment recognized

or

^ Seat belt buckle defective

For the dynamic function circuit 15 must be switched on and v > 10 km/h. However, the status LEDs in the dynamic button (S108s6) indicate the status as of c. 15R "ON".

Function description for dynamic multicontour seat lateral support, general
The dynamic lateral support function combines the advantages of a comfortable seat with those of a sport seat. For this, the lateral support is improved during cornering by means of an automatic pressure increase of the lateral support cushions (side bolsters) on the outside of the curve. Intensity can be adjusted in two stages.

The dynamic lateral support function is described at the driver seat for left-hand drive vehicles by way of an example, but this also applies for the front passenger seat.

Abort conditions
- Inflation or deflation timeout
- Leak in one of the lateral support cushions
- On-board electrical system emergency running mode
- Timeout or no signal for steering angle data, lateral acceleration or yaw rate
- Adjustment request based on memory
- Channel 1 of driver dynamic multicontour seat button group is short-circuited to ground or stuck.

In the event of valve overtemperature, the function is also shut down.

Blocking
When the following faults are present, the function for the current ignition sequence is inhibited, however, the display in the dynamic button is maintained.
- Inflation or deflation timeout
- Channel 1 for driver or passenger dynamic seat button group is short-circuited to ground or stuck.

The dynamic lateral support function is structured as follows:
^ Start and end
^ Program sequence
^ Valve control
^ Compressed-air supply

Start and end
The program "Dynamic lateral support" can be adjusted in two stages and is indicated by two LEDs in the dynamic button. The program starts with stage 2 (dominant) after the dynamic button is actuated which is indicated by illumination of the two LEDs in the dynamic button. When the dynamic button is actuated again, stage 1 (discreet) is actuated; this is indicated by illumination of one LED. A third actuation of the dynamic button terminates the DYNAMIC program and both LEDs go out.

Program sequence
The DYNAMIC function should combine the advantages of a comfortable seat with those of a sport seat.

For this purpose, the lateral support is adjusted automatically by initial pressure in the side support air cushion. When cornering, a brief application of pressure in the outside lateral support cushions serves to additionally improve the lateral support.

This essentially happens as a function of the current vehicle speed and the lateral acceleration. The intensity of the program can be adjusted in two stages using the dynamic button:

Dominant stage
- Higher pressure is applied more rapidly to the lateral support air cushions on the outside of the curve.

Decent state
- Lower pressure is applied more slowly to the lateral support air cushions on the outside of the curve.

Valve control
Depending on the vehicle speed and lateral acceleration, the left front dynamic multicontour seat control unit (N32/19) actuates the valves of the lateral support air cushions. These data is transmitted via the interior CAN by the front SAM control unit with fuse and relay module (N10/1), which acts as gateway and the data is routed by the electronic stability program control unit (N30/4) (vehicles without code (233) DISTRONIC PLUS) or electronic stability program control unit Premium (N30/7) (vehicles with code (233) DISTRONIC PLUS).

Compressed-air supply
The air supply, required for inflating the seat cushions, is provided by the pneumatic pump for dynamic multicontour seat (M40/1).