BMW 7 Series: Other Seat Functions

Reset function

The reset function enables you to set the comfort seat to a pre-set seat position. After the reset button is pressed, the seat automatically moves into position. It can be used to make the seat more easily accessible during servicing. This, for example, is of benefit to customers and service technicians, because getting out of the vehicle and accessing the comfort seat becomes easier.

NOTE: The reset function can also be used for fitting a child seat. After the reset function is activated, the comfort seat is in a better position for fitting the child seat.

Fig. 112: Identifying Reset Button

COMPONENTS DESCRIPTION CHART

1. Reset button for the rear compartment comfort seat

Position detection

The adjustment motors are equipped with Hall sensors. The Hall sensors generate Hall pulses during activation, which are evaluated by the seat module. The seat module calculates the fixed distance intervals based on the Hall pulses and determines the current seat adjustment position.

The seat position is stored in the seat module and used for the memory position.

Obstruction detection

The seat module records the Hall sensor pulses of the adjustment motors. If the adjustment motor is obstructed the Hall sensor pulses will fail. The seat module also detects an obstructed motor from the increased current when the obstruction occurs. The seat module then cancels activation of the adjustment motors.

The adjustment motor can be activated in the same direction again. If the motor remains obstructed, it must be activated in the opposite direction. If the seat can be moved in the opposite direction, then the seat module allows you to activate the original direction again.

If the obstruction in the adjustment motor cannot be cleared, then this motor is no longer used to store the memory function.

Rear seat adjustment button

In unfavorable situations, the leg room behind the front-passenger seat can seem quite narrow. Someone sitting behind the front-passenger seat may find this unpleasant.

In order to enlarge the space in front of the rear seat on the front-passenger's side, there is an additional button fitted on the center armrest in the rear seat area. This button allows you to operate the front-passenger seat.

The rear seat module behind the front-passenger seat requests the button status via the LIN bus.

This enables it to detect when the button is pressed. If the button is pressed, the rear seat module behind the front passenger seat prepares itself to carry out a seat adjustment to the front-passenger seat.

When the seat adjustment buttons for the rear seat are now operated, they adjust the front-passenger seat accordingly.

The function is deactivated by pressing the button for operating the front-passenger seat again.

NOTE: A seat adjustment made via the buttons on the front-passenger seat has priority over those made from the rear seat.

Fig. 113: Signal Path Button For Making Seat Adjustments To Front-Passenger Seat From F01/F02 Rear Seat

COMPONENTS DESCRIPTION CHART

1. Buttons for seat functions
2. Seat module, passenger side rear (SMBFH)
3. Passenger's seat module (SMBF)

Memory Function for the Rear-compartment Comfort Seat

The memory function is available for both the left and right rear passenger seat and can be activated from terminal 30B ON. The memory buttons are connected to the junction box electronics via the LIN bus.

The seat module of the seat concerned is responsible for the memory function. The junction box electronics request the status of the memory buttons via the LIN bus on a cyclical basis. To enable the seat module to read out the status of the memory buttons, the button status must be transferred on several bus systems. The bus systems are:

• LIN bus (JB > buttons)
• LIN bus (buttons > JB)
• K-CAN2 (JB > ZGM)
• K-CAN (ZGM > SM).

Press the memory button to prepare for storing the memory position. The seat module sends the request to switch on the function indicator. From the function indicator, for example, the customer can recognize that the memory function is ready for storing.

Pressing button "1" or "2" assigns the current position of the driver's seat to the pressed button. One memory position is available for each of the buttons "1" and "2".

The data is assigned to the current ID transmitter as part of the Personal Profile, when the memory position is stored.

If the seat module detects an obstructed adjustment motor, then memory adjustments to the motor remain disabled until the motor is no longer obstructed.

Fig. 114: Memory Buttons In Armrests Of F01/F02 Driver's Side

COMPONENTS DESCRIPTION CHART

1. M button
2. Button 1
3. Button 2

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