BMW 7 Series: System Components

Controls and Control Units

Controls

The controls for the seat functions are connected depending on the seat equipment. The controls are:

• Seat-adjustment switches
• Lumbar support switch
• Memory buttons
• Active-seat button
• Active seat ventilation button
• Massage function button.

Refer to the following table:

COMPONENTS DESCRIPTION CHART

Control Units

Junction box electronics

The junction box electronics each have a control outlet for the seat heating. In seat heating with a seat heating module, the junction box electronics activate the seat heating via the LIN bus.

NOTE: The junction box electronics cede activation of the seat heating to the seat module of the respective seat.

Seat heating module

The seat heating module evaluates the LIN bus signal from the junction box electronics. The seat heating module is connected by means of three connectors. One connector establishes the connection to the junction box electronics. The other two connectors are responsible for connecting the seat heating.

Seat module

The seat module receives activation information for the seat heating via the K-CAN. Similarly, the seat module evaluates the button status of the controls for the various seat functions.

The requests made by the memory buttons for the door mirror are made available via the K-CAN. The positions for seat memory are stored in the seat module.

The requirements of the seat-adjustment switches are executed by the seat module.

Pressure Distribution Module

Fig. 123: Identifying Lumbar Support Pump, Pressure Distribution Module And Seat Module

COMPONENTS DESCRIPTION CHART

1. Lumbar support pump
2. Seat module
3. Pressure distribution module, massage/lumbar support

A pressure distribution module located in the backrest is for inflating and deflating the respective massage or mobilization cushions. The pressure distribution module distributes the air for the massage cycle. There is a motor for this that drives an eccentric shaft. The eccentric shaft is designed so that it alternately opens and closes the air inlets and outlets of the massage cushions and mobilization cushions.

The required air is supplied by the pump for the lumbar-support adjustment. The seat module receives the request for the required air for the massage function from the pressure distribution module. The pump for the lumbar-support adjustment is activated by the seat module.

NOTE: Lumbar-support adjustment has priority over the massage function.

READ NEXT: