BMW 7 Series: Massage Function In Rear-Compartment Comfort Seat

The optional rear-compartment massage gives the rear-seat passenger even more comfort than in the E65. The rear-compartment massage function is being offered in the F01/F02 for the first time at BMW.

An electropneumatic system is used to implement the massage function.

The massage function is available for both the left and right rear passenger seat and can be activated from terminal 30B ON. The seat module is integrated into the back of the backrest in the left rear and the right rear seat and has sole responsibility for the massage function.

The buttons for the massage function are connected via the LIN bus to the junction box electronics.

Fig. 118: Identifying Button Block In Armrests Of F01/F02 Driver's Side

COMPONENTS DESCRIPTION CHART

1. M button
2. Button 1
3. Button 2
4. Massage function button

The junction box electronics evaluate the status of the massage button and sends the status via the K-CAN2.

The central gateway module transfers the signal to the K-CAN. This allows the seat module to receive the current status of the buttons. The seat module evaluates the status, activates the massage function, and monitors it.

In the backrest of the comfort seat, there is a massage pad for the massage function. Pressing the button starts the massage function at the maximum massage intensity. Pressing the button again switches it to a lower massage intensity level.

Pressing the button once again switches the massage function off.

If the button is pressed for longer than 1.2 seconds during the massage function, the massage function will be switched off.

In order to indicate that the massage function has been activated, the seat module sends the request to switch on the LEDs in the button.

The signal terminal 58g ON is made available through the footwell module. The junction box electronics pass on terminal 58g ON to the button. The button then switches the back lighting on.

Massage

The massage function is divided into massage cycles. A massage cycle consists of the massage and includes back mobilization and lasts approximately 64 seconds. After this, a new massage cycle begins.

There are twelve massage cushions that help to relieve tension in the back muscles through a wave-like motion along the backrest from top to bottom.

The wave-type motion is created by inflating and deflating the massage cushions. The pressure distribution module activates the massage cushions in pairs simultaneously.

The massage function is designed so that the two upper massage cushions are activated first. Activation in this situation means inflating and deflating the massage cushions with air. Following this, the pair of massage cushions lying beneath are activated and this continues until the bottom massage cushions are reached.

Towards the end of the massage cycle, mobilization of the back begins.

Fig. 119: Identifying F01/F02 Massage Cushions

COMPONENTS DESCRIPTION CHART

1. Massage cushion pair 1
2. Massage cushion pair 2
3. Massage cushion pair 3
4. Massage cushion pair 4
5. Massage cushion pair 5
6. Massage cushion pair 6

Mobilization cushions are used for mobilization. There are six mobilization cushions arranged in the outside shoulder area, in the center of the thorax and in the lumbar area.

The mobilization cushions are simultaneously inflated and deflated periodically and sectionally. For example, the mobilization cushions in the right shoulder and right lumbar as well as the mobilization cushions in the left thorax are pumped up and deflated. Following that, the opposite side is inflated and deflated.

If the lumbar support is set when the massage function has been activated, the seat module deactivates the massage function. This allows the pump for the lumbar support adjustment to supply enough air flow to inflate the lumbar cushions.

After the lumbar support has been set, the massage function continues.

The massage function has a defined run-on. With this run-on the massage cushions and mobilization cushions are fully deflated. The run-on encompasses one massage cycle.

The pump for the lumbar support runs at various speeds depending on the function. Refer to the following table:

COMPONENTS DESCRIPTION CHART

COMPONENTS DESCRIPTION CHART

1. Mobilization cushions, right shoulder, left thorax and right lumbar
2. Mobilization cushions, left shoulder, right thorax and left lumbar

Fig. 120: Identifying F01/F02 Massage Cushions

Fig. 121: Massage Cycle Sequence Diagram

MASSAGE CYCLE SEQUENCE CHART

1. Massage cushion pair 1
2. Massage cushion pair 2
3. Massage cushion pair 3
4. Massage cushion pair 4
5. Massage cushion pair 5
6. Massage cushion pair 6
7. Mobilization cushions, right shoulder, left thorax and left lumbar
8. Mobilization cushions, left shoulder, right thorax and left lumbar

Orange - Graph of max. massage intensity
Blue - Graph of min. massage intensity

System Circuit Diagram, Rear Comfort Seat Behind the Driver

Fig. 122: Rear Comfort Seat System Circuit Diagram

COMPONENTS DESCRIPTION CHART

1. Footwell module (FRM)
2. Central gateway module (ZGM)
3. Junction box electronics (JB)
4. Motor, longitudinal seat adjustment (SLV)
5. Motor, seat-inclination adjustment (SNV)
6. Motor, backrest-inclination adjustment (LNV)
7. Motor, upper backrest adjustment (LKV)
8. Motor, head-restraint height adjustment (KHV)
9. Pump, lumbar support/massage function 23 Distribution box in luggage compartment
10. Pressure distribution module, massage/lumbar support
11. Solenoid valves for lumbar support
12. Pump for lumbar support(1)
13. Fan, active seat ventilation, backrest surface
14. Fan, active seat ventilation, seat surface
15. Seat-heating pad, backrest surface
16. Seat-heating pad, seat surface
17. Seat module, driver's side, rear (SMFAH)
18. Button block in the armrest, driver's side
19. Buttons, seat functions, driver's seat
20. Integrated automatic heating and air conditioning IHKA
21. Advanced Crash Safety Management (ACSM)
22. Seatbelt-buckle switch

K-CAN2 - Body CAN2
K-CAN - Body CAN
LIN-Bus - Local interconnect network bus
KI. 30B - Terminal 30 basic operation

(1) Pump in a vehicle equipped with lumbar support. In a vehicle equipped with massage seats, a different pump is used.

This pump supplies the massage seat and lumbar support with air.

K-CAN signals at the seat module

K-CAN SIGNALS CHART

The seatbelt-buckle switch signals whether the seatbelt is fastened or not. When the seatbelt is fastened, the seat module adjusts the head restraint with an electric motor to the previously used head restraint height.

If the seatbelt has not been fastened, then the head restraint is fully retracted. This increases the field of vision out the back window.

The Advanced Crash Safety Management evaluates the seatbelt-buckle switch and sends its status via the PTCAN.

The central gateway module transfers the signal to the KCAN. This provides the seat module with information about whether the seatbelt is fastened or not. The seat module sets the head restraint to the maximum height if the seatbelt is on, or completely back if the seatbelt is not on.

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