Component description of driver-side front seat adjustment control unit with memory - GF91.29-P-5223G

MODEL 463.306/336/346 as of model year 2011/YoM 10

MODEL 463.202/222/236/237 as of model year 2009/YoM 08

MODEL 463.247/248/249/254 up to 31.8.08 as of model year 2007

MODEL 463.270/271/303/340/341 as of model year 2007

Shown up to 31.8.09

Fig 1: Locating Driver-Side Front Seat Adjustment Control Unit With Memory

Courtesy of MERCEDES-BENZ USA

Location

The front seat adjustment control unit is located underneath the seat frame of the driver.

Task

The front seat adjustment control unit has the following tasks:

Controlling functions

Electric seat adjustment as per the requests of the left front seat adjustment switch group (with memory) (S91) via interior CAN (CAN-B)
Steering column adjustment functions as per the requirements of the steering column adjustment switch (S59) via interior CAN Recording and saving the actual position, as well as moving to stored positions of the adjustment functions
"Key-dependent" position storage, i. e. dependent on the memory block number
Easy entry for rear passengers (easy entry) (on model 463.254/303)
Easy entry and exit feature for driver seat

Reading in of sensors, pickups and signals

The input factors are read in via the following connections:

Direct line

Steering column in/out motor (M20/1) Hall sensors
Steering column up/down motor (M20/2) Hall sensors
Left fore/aft seat adjustment motor (M27/1) Hall sensors
Left rear seat height adjustment motor (M27/2) Hall sensors
Left front seat height adjustment motor (M27/3) Hall sensors
Left head restraint seat adjustment motor (M27/4) Hall sensors
Left backrest motor (M27/5) Hall sensors
Left front seat backrest release microswitch (S91/3) (on model 463.254/303)

Interior CAN

The signals are read in by the front seat adjustment control unit via interior CAN.

The functions resulting therefrom are described in the corresponding function description (see block diagram or function schematic).

Evaluation of input factors

The input factors that have been read in are evaluated by the integrated microprocessor and the relevant components are then actuated.

Component actuation

Components are actuated with the following line:

Direct line

The following components are actuated via a direct line: