Component description of passenger-side front seat adjustment control unit with memory - GF91.29-P-5224GM

MODEL 164.1 as of model year 09/YoM 08 model refinement package with CODE (242) Electrically adjustable front passenger seat with memory

MODEL 164.8, 251.0/1 as of model year 09/YoM 08 with CODE (242) Electrically adjustable front passenger seat with memory

Fig 1: Identifying Front Passenger Front Seat Adjustment Control Unit With Memory

Courtesy of MERCEDES-BENZ USA

Location

The passenger-side front seat adjustment control unit with memory is located below the seat frame of the front passenger seat.

Tasks

Actuation of the motors for the seat adjustment as per the requests read in by the driver seat adjustment with memory switch group (S91)
Storing of the memory adjustments for the front passenger seat - Control of the EASY-ENTRY function with collision avoidance (model 164.8 with code (845) 3rd seat row folding down electrically)
Moving the front passenger seat in the event of a presafe request
Power supply from front passenger lumbar support regulator control unit (N32/24)

These are grouped as follows:

Reading in of sensors and signals
Evaluating input factors
Actuation of components

Reading in of sensors and signals

These input factors are read in via the following connections:

Direct line
Interior CAN (CAN B)

Direct line

Circuit 30
Circuit 31

The following sensors are read in via direct lines:

Hall sensors of the seat adjustment motors
Front passenger seat adjustment with memory switch group (S92)

Interior CAN (CAN B)

Circuit status and battery voltage from EIS [EZS] control unit (N73)
Status of the rear bench seat from rear SAM control unit (N10/8) (necessary for EASY-ENTRY function)
Signals for presafe request from central gateway control unit (N93)

First, the signals for the presafe request are placed on the engine compartment CAN (CAN C) by the ESP control unit (N47-5) and read in by the central gateway control unit.

Evaluation of input factors

The read in input factors are evaluated by the front passenger seat control unit. The actuation of the motors for the seat adjustment takes place via integrated relays.

Actuation of components

Circuit 30 and circuit 31 to the front passenger lumbar support regulator control unit

The following motors are actuated via direct lines:

Front passenger seat longitudinal adjustment motor(M28/1)
Front passenger rear seat height adjustment motor (M28/2)
Front passenger front seat height adjustment motor (M28/3)
Front passenger head restraint motor (M28/4)
Front passenger backrest angle adjustment motor (M28/5)

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 of front passenger-side seat control unit	MODEL 164 control unit N32/2	PE91.29-P-2105-99MAA
		MODEL 251 control unit N32/2	PE91.29-P-2105-99RAA