GF91.29-P-5273CA Lumbar Support Adjusting Facility Control Unit, Component Description

GF91.29-P-5273CA Lumbar Support Adjusting Facility Control Unit, Component Description
- except CODE (409) Left/right front multicontour seat

Component Identification:

Location
The lumbar support adjustment control unit is installed off-center in the respective backrest frame behind the backrest trim.
- Regulation of the air cushion pressures in the two lumbar cushions of the respective front 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)
- Reading in the voltage-coded driver seat lumbar support adjusting facility switch (S109/2) and the front passenger seat lumbar support adjusting facility switch (S109/3)

These are grouped as follows:
^ Reading in of switches, sensors and signals
^ Evaluation of input factors
^ Actuation of components

Reading in of switches, sensors and signals
These input factors are read in via direct connections:
- C. 30g (with code (275) Memory package (driver seat, steering column, mirrors)) or code (242) Electrically adjustable passenger seat with memory)
- C. 15R (except code (275) Memory package (driver seat, steering column, mirrors)) and except code (242) Electrically adjustable passenger seat with memory)
- Circuit 31

The following switches are read in via direct lines:
- Driver seat lumbar support adjustment switch (S109/2) and front passenger seat lumbar support adjustment switch (S109/3)
- Internal pressure sensor

The signals are read in/transmitted by the lumbar support adjustment control unit. The functions resulting therefrom are described in the corresponding function descriptions (see block diagram or function schematic).

Evaluation of input factors
The read-in input factors are evaluated by the lumbar support adjusting facility control unit. The air cushions in the seat are actuated via valves integrated in the lumbar support adjusting facility control unit.

Actuation of components
The following components are actuated via direct lines:
- Driver seat lumbar support pneumatic pump (M25/4) or front passenger seat lumbar support pneumatic pump (M25/5), for controlling the compressed air supply

The air cushions in the seat are actuated via valves integrated in the lumbar support adjusting facility control unit.

Design
In addition to the intelligent circuit, a pressure sensor is also located in the housing of the lumbar support adjustment control unit. This sensor is used for detecting and monitoring the pressure. The air pressures in the cushions are adjusted by the valves integrated in the lumbar support adjusting facility control unit. The lumbar support adjusting facility control unit is connected to the lumbar support adjusting facility switch on the seat via the 7-pin connector. It is also connected to the lumbar support pneumatic pump and the power supply via this connector.

Variants
- None