(Component Description For Driver Seat Control Unit - GF91.29-P-5231GR)

Model 166 

up to model year 2016 

with code 275 (Memory Package (driver's seat, steering column and mirror)) 

Shows model 166.0 

Courtesy of MERCEDES-BENZ USA

Location 

The driver seat control unit is located at the bottom of the driver seat frame.

Task 

The driver seat control unit controls the following functions:

• Seat and steering column adjustment
• Easy entry/exit
• Memory function for seat, outside mirrors and steering column
• Collision avoidance with bench seat in rear

The tasks are subdivided as follows:

• Reading in of sensors and signals 
• Evaluation of input factors 
• Actuation of components 
• Transmitting signals 

Reading in of sensors and signals 

The input factors are read in via the following connections:

• Direct line 
• Interior CAN (CAN B) 

Direct line 

The signals from the following sensors are read via direct lines:

• Steering column in/out Hall sensor (M20/1b1)
• Steering column up/down Hall sensor (M20/2b1)
• Seat fore/aft adjustment Hall sensor, driver seat (M27/1b1)
• Height adjustment Hall sensor, driver seat (M27/2b1)
• Inclination adjustment Hall sensor, driver seat (M27/3b1)
• Head restraint adjustment Hall sensor, driver seat (M27/4b1)
• Backrest inclination Hall sensor, driver seat (M27/5b1)

Interior CAN 

The driver seat control unit reads in the following signals via interior CAN, among other things:

• Seat adjustment request
• Steering column adjustment request
• Request for storing/moving to memory position

The functions that use these signals are described in the individual function descriptions (see block diagram or function schematic).

Evaluation of input factors 

The read in input factors are evaluated by the driver seat control unit. The motors for seat and steering column adjustment are actuated via integrated relays.

Actuation of components 

The following components are actuated via direct lines:

• Steering column in/out adjustment motor (M20/1)
• Steering column up/down adjustment motor (M20/2)
• Driver seat fore/aft adjustment motor (M27/1)
• Driver seat height adjustment motor (M27/2)
• Driver seat inclination adjustment motor (M27/3)
• Driver seat head restraint adjustment motor (M27/4)
• Driver seat backrest inclination adjustment motor (M27/5)

With CODE 401 (Front comfort seats, incl. seat heating and seat ventilation):

• Left front seat cushion seat ventilation motors (M18/9)
• Left front backrest seat ventilation motors (M18/10)

With CODE (873) (Seat heater for left and right front seat):

• Left front seat cushion heater pad (R13/1)
• Left front backrest heated cushion (R13/2)

With CODE 876 (Interior lights package):

• Left rear footwell lamp (E17/17)

The driver seat control unit supplies power to the driver seat lumbar support adjustment control unit (N32/23) and the driver multicontour seat control unit (N32/29) (with code (399) Front multicontour seats with massage function).

Transmitting signals 

The driver seat control unit sends the following signals via interior CAN, among other things:

• Request for acknowledge tone after storage in memory
• Request for storing/occupying memory position
• Seat position status

The functions that use these signals are described in the individual function descriptions (see block diagram or function schematic).

Variants 

There are no variants for the hardware of the driver seat control unit.

The country or left-hand drive vehicle/right hand drive vehicle allocation is software coded.

Wiring diagram of driver-side seat control unit

PE91.29-P-2104-97NAA