Component Description For Front Passenger Seat Control Unit - GF91.29-P-5241FH

Model 238 

Up To Model Year 2021 

With Code 275 (Memory Package (driver's seat, steering column and mirror)) 

The component description for the front passenger seat control unit (N32/2) describes a left-hand drive vehicle. Right-hand drive vehicles are to be observed mirror inverted with regard to the designations of the electric components.

Courtesy of MERCEDES-BENZ USA

Location 

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

Task 

The front passenger seat control unit is responsible for the following tasks:

• Control of seat adjustment
• Storing/moving into the memory settings for the front passenger seat
• Controlling the collision avoidance feature
• Actuating PRE-SAFE® positioning function for front passenger seat

The tasks are subdivided as follows:

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

Read in sensors and signals 

The input factors are read in via the following connections:

• Direct line 
• Interior CAN (CAN B) 

Direct line 

The front passenger seat control unit reads in the signals from the following sensors over direct lines:

• Seat fore/aft adjustment Hall sensor, front passenger seat (M28/1b1)
• Head restraint adjustment Hall sensor, front passenger seat (M28/4b1)
• Backrest inclination Hall sensor, front passenger seat (M28/5b1)
• Seat cushion length adjustment Hall sensor, front passenger seat (M28/8b1)
• Seat inclination adjustment Hall sensor, front passenger seat (M28/9b1)
• Seat height adjustment Hall sensor, front passenger seat (M28/10b1)
• Right backrest release microswitch (S92/6s1) in right backrest release/backrest inclination microswitch (S92/6)
• Right backrest inclination microswitch (S92/6s2) in the right backrest release/backrest inclination microswitch

With code 902 (Seat heater plus for driver and front passenger):

• Right front seat cushion seat side bolster heater pad temperature sensor (R13/13b1)
• Right front seat backrest seat side bolster heater pad temperature sensor (R13/14b1)

Interior CAN 

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

• Seat adjustment request
• Request for storing/moving to memory position
• Backrest in rear, status

Evaluation of input factors 

The read in input factors are evaluated by the front passenger seat control unit. The seat adjustment motors are actuated via integrated relays.

Actuation of components 

The front passenger seat control unit actuates the following components via direct lines:

• Right front seat cushion seat ventilation motors (M18/11) (with CODE 401 (Seat climate control for driver and front passenger))
• Right front backrest seat ventilation motors (M18/12) (with CODE 401 (Seat climate control for driver and front passenger))
• Front passenger seat fore/aft adjustment motor (M28/1)
• Front passenger seat head restraint adjustment motor (M28/4)
• Front passenger seat backrest inclination adjustment motor (M28/5)
• Seat cushion length adjustment motor, front passenger seat (M28/8)
• Seat inclination adjustment motor, front passenger seat (M28/9)
• Seat adjustment motor, seat height adjustment, front passenger seat (M28/10)
• Right front seat cushion heater pad (R13/3) (with code 401 (Seat climate control for driver and front passenger) or code 873 (Seat heater for driver and front passenger))
• Right front seat backrest heater pad (R13/4) (with code 401 (Seat climate control for driver and front passenger) or code 873 (Seat heater for driver and front passenger))
• Right front seat cushion seat side bolster heater pad (R13/13) (with code 902 (Seat heater plus for driver and front passenger))
• Right front seat backrest seat side bolster heater pad (R13/14) (with code 902 (Seat heater plus for driver and front passenger))
• Heater pad for adjustable seat cushion length, right front seat (R24/1) (with code 401 (Seat climate control for driver and passenger) or code 873 (Seat heater for driver and passenger) or code 902 (Seat heater plus for driver and passenger))

Transmitting signals 

The front passenger seat control unit sends signals via the following connections:

• Front passenger seat LIN (LIN B19) (With Code 902 (Seat heater plus for driver and front passenger)) 
• Interior CAN 

Front passenger seat LIN (With Code 902 (Seat heater plus for driver and front passenger)) 

Amongst other things, the front passenger seat control unit transmits the "Switch on seat heater" request via the front passenger seat LIN to the front passenger seat heater control unit (N25/4).

Interior CAN 

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

• Request for acknowledge tone after storage in memory
• Seat position status
• Seat ventilation status (with CODE 401 (Seat climate control for driver and front passenger))
• Seat heater status (with code 401 (Seat climate control for driver and front passenger) or code 873 (Seat heater for driver and front passenger) or code 902 (Seat heater plus for driver and front passenger))

Variants 

There are no variants for the hardware of the front passenger seat control unit. The country or left-hand drive vehicle/right hand drive vehicle allocation is software coded.

Wiring diagram for front passenger seat control unit

PE91.29-P-2104-97DCA