Lumbar Support Control Unit, Component Description - GF91.29-S-5281TRA

Model 447

With Code SE5 (Lumbar support for driver's seat)

Except Code XM7 (MOPF II)

Model 448.8

With Code SE5 (Lumbar support for driver's seat)

Shown on driver seat

Fig 1: Lumbar Support Control Unit Components Location - Model 447 With Code SE5 Except Code XM7 (Shown On Driver Seat)

Courtesy of MERCEDES-BENZ USA

Location

The driver seat lumbar support adjustment control unit (N32/23) and the front passenger seat lumbar support adjustment control unit (N32/24) are each located in the seat backrest frame in the center behind the backrest trim.

Task

The driver seat lumbar support adjustment control unit (N32/23) and the front passenger seat lumbar support adjustment control unit (N32/24) have the following tasks:

Regulate the air pressure in the lumbar support for each seat
Storage of last adjusted lumbar support contour
Control of the driver seat lumbar support pneumatic pump (M25/4) or front passenger seat lumbar support pneumatic pump (M25/5)

The tasks are subdivided as follows:

Reading in of signals
Evaluation of input factors
Actuation of components

Reading in of signals

The signals of the driver seat lumbar support adjustment switch (S204) are read in by the driver seat lumbar support adjustment control unit (N32/23) over a direct line
The signals of the front passenger seat lumbar support adjustment switch (S2041) are read in by the front passenger seat lumbar support adjustment control unit (N32/24) over a direct line

Evaluation of input factors

The read-in input factors are evaluated by the driver seat lumbar support adjustment control unit (N32/23) or by the front passenger seat lumbar support adjustment control unit (N32/24).

Actuation of components

The driver seat lumbar support pneumatic pump (M25/4) is actuated by the driver seat lumbar support adjustment control unit (N32/23) over a direct line
The front passenger seat lumbar support pneumatic pump (M25/5) is actuated by the front passenger seat lumbar support adjustment control unit (N32/24) over a direct line

The air pressure in each of the lumbar supports is regulated by the valves integrated into the driver seat lumbar support adjustment control unit (N32/23) and the front passenger seat lumbar support adjustment control unit (N32/24).

Structure

Along with the microprocessor, a pressure sensor is also installed in the driver seat lumbar support adjustment control unit (N32/23) and in the front passenger seat lumbar support adjustment control unit (N32/24).

	Wiring diagram for driver seat adjustment, seat heater	Model 447 with code SE5 (Lumbar support for driver's seat) except code XM7 (MOPF II)	PE91.00-S-2105-97VVA
	Wiring diagram of driver seat control unit	Model 448.8 with code SE5 (Lumbar support for driver's seat)	PE91.29-S-2114-97VDA