GF91.25-P-2033FQ Dynamic Function for Active Multicontour Seat, Function

GF91.25-P-2033FQ Dynamic Function For Active Multicontour Seat, Function
MODEL 218
- with CODE (432) Active multicontour seat

Function requirements, general
^ Circuit 15 ON
^ Vehicle speed greater than 10 km/h
^ Pressure supply active
^ No on-board electrical system limp-home mode
^ High-voltage supply in left front active multicontour seat control unit (N32/19) or in right front active multicontour seat control unit (N32/22) (except code (494) USA version) OK
^ Each driver active multicontour seat button group (S109) or front passenger active multicontour seat button group (S108) (except code (494) USA version) is detected as plugged in
^ Status of pneumatics pump for active multicontour seat (M40/1) on interior CAN (CAN B) OK

The circuit status is sent to the active multicontour seat control unit over the interior CAN by the electronic ignition lock control unit (N73).

Additional function requirements on passenger side (except code (494) USA version)
^ Seat occupied detected
or
^ Seat belt buckle inserted

Circuit 15 must be switched on for the dynamic function and the speed must be greater than 10 km/h. The LEDs on the status indication in the Dynamics button (S109s6) already indicate the status at circuit 15R "ON".

Dynamic function for active multicontour seat, general
The dynamic function (dynamic lateral support) 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 function is described at the driver seat for left-hand drive vehicles by way of an example, but this also applies for right- hand drive vehicles.
For vehicles with code (494) USA version only the driver seat is an active multicontour seat.

Abort conditions
- Inflating or deflating time-out
- Leak in one of the two lateral support cushions
- On-board electrical system emergency running mode
- Time-out or no signal for steering angle data, lateral acceleration or yaw rate
- Adjustment request based on memory
- Channel 1 of the driver's active multicontour seat button group has a short circuit to ground or is jammed.

Blocking
For the following active fault, the function is blocked for the ignition sequence running, the display in the Dynamics button is retained however:
- Inflating or deflating time-out
- Channel 1 of the driver's active multicontour seat button group has a short circuit to ground or is jammed.

The dynamic function has the following structure:
^ Start and end
^ Program sequence
^ Valve control
^ Compressed-air supply

Start and end
The "DYNAMIC" (dynamics function) program can be adjusted in two stages and it is indicated by two LEDs in the Dynamics button. The program starts here after the Dynamics button is pressed in stage 2 (dominant), this is indicated by the LEDs lighting in the Dynamics button. If the Dynamics button is pressed again stage 1 (discreet) is executed, this is indicated by the LED lighting. A third press of the Dynamics button results in the "DYNAMIC" program ending whereupon the two LEDs go out.

Program sequence
The Dynamic function should combine the advantages of a comfortable seat with those of a sport seat.
The lateral support is automatically adjusted here to suit using a base pressure in the air cushion lateral support. When cornering, a brief application of pressure in the outside air cushion 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 Dynamics button:

Dominant
- The air cushion lateral supports on the outside of the curve have more pressure applied to them faster.

Discreet
- The cushion lateral supports on the outside of the curve have less pressure applied to them slower.

Valve control
Depending on the vehicle speed and lateral acceleration, the left front active multicontour seat control unit (N32/19) actuates the valves of the lateral support air cushions. The vehicle speed and lateral acceleration data are sent over the interior CAN by the front SAM control unit with fuse and relay module (N10/1), which acts as a gateway and routes the data from the chassis CAN (CAN E). The data are sent beforehand by the Electronic Stability Program control unit (N30/4) (vehicles without code (233) DISTRONIC PLUS) or from the Premium Electronic Stability Program control unit (N30/7) (vehicles with code (233) DISTRONIC PLUS) over the chassis CAN.

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