Adjust front multi-contour seats, function - GF91.25-P-2002R

MODEL 230 

with CODE (404b) Multi-contour backrest driver seat 

with CODE (405b) Multi-contour backrest passenger seat 

Fig 1: Front Multi-Contour Seats Function Diagram

Courtesy of MERCEDES-BENZ USA

Networking of the components of the multi-contour backrest 

The multi-contour backrests for driver seat/front passenger seat  can be adjusted

• manually 
• automatically 

Function requirements 

• C. 15 ON
• C. 15R ON
• The control module for left front multi-contour backrest (N32/15)/ control module for right front multi-contour backrest (N32/16)  is activated  whenever it receives a release signal  from the front seat adjustment control module with memory, left (N32/1)/ front seat adjustment control module with memory, right (N32/2)  .

Manual adjusting of the air cushion groups in the multi-contour backrest 

The pneumatic system equipment with combination functions (A37)  receives the CAN message from the EIS control module (N73)  via the interior CAN and supplies the pressure control valves in the control module for left front multi-contour backrest (N32/15)/ control module for right front multi-contour backrest (N32/16)  with an overpressure.

The switching states of the switch group for left front multi-contour backrest (S109)/ switch group for right front multi-contour backrest (S108)  are input by the control module for left front multi-contour backrest (N32/15)/ control module for right front multi-contour backrest (N32/16)  and then the corresponding air cushion groups are filled/emptied.

At the same time, between these control modules and the front seat adjustment control module with memory, left (N32/1)/ front seat adjustment control module with memory, right (N32/2) 

data is exchanged via the data line so that it is possible to store  and later call up  manual air cushion adjustments via the memory feature  .

Automatic adjustment of the air cushion groups in the multi-contour backrest via the memory feature 

additional function prerequisites 

• C. 15C ON
• respective door open for t >20 s

The rear SAM control module (N10/8)  signals the states of the left door contact switch (S17/3), right door contact switch  of the left door contact switch (S17/3), right door contact switch (S17/4)  and the switch-on state of the EIS control module (N73)  via the interior CAN. The pneumatic system equipment with combination functions (A37)  supplies the pressure control valves in the control module for left front multi-contour backrest (N32/15)/ control module for right front multi-contour backrest (N32/16)  with an overpressure.

The storing  and calling up  of manual adjustments is triggered by the corresponding switch in the switch group for left seat adjustment (S91/2)/ switch group for right seat adjustment (S92/2)  . The left door control module (N69/1)/ right door control module (N69/2)  reads this information and transmits it as a CAN message to the front seat adjustment control module with memory, left (N32/1)/ front seat adjustment control module with memory, right (N32/2)  .

If these receive a request to store  , the pressure values of the air cushions transmitted by the control module for left front multi-contour backrest (N32/15)/ control module for right front multi-contour backrest (N32/16)  are stored in a nonvolatile memory  . When calling up  memory positions, the stored air cushion pressure values are resent to the control module for left front multi-contour backrest (N32/15)/ control module for right front multi-contour backrest (N32/16)  . These then fill/empty the air cushions according to the stored values.

The storing  and calling up  of the memory positions is described in the document "Electric seat adjustment with memory feature" ( GF91.29-P-0002R  )  .