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Functional networking

The parking assist consists of the PMA control unit and 2 ultrasonic sensors which take charge of measuring out the parking space. The steering movements required for parking the car which are calculated by the control unit are then carried out by the electromechanical power steering system (EPS).

The parking maneuvering assistant calculates the optimal line for parking. The parking maneuvering assistant takes over the steering during the parking procedure. During parking, additionally observe the visual and acoustic information of the PDC and the parking maneuvering assistant and accelerate or brake accordingly.

In view of the complex nature of the parking maneuvering assistant, many control units are interlinked by the bus system.

Fig 1: PMA Control Unit - Circuit Diagram
G09909337Courtesy of BMW OF NORTH AMERICA, INC.
Index Explanation
1 Ultrasonic sensor, front outer left
2 Ultrasonic sensor, front center left
3 Ultrasonic sensor, front center right
4 Ultrasonic sensor, front outer right
5 Ultrasonic sensor, parking maneuvering assistant, right
6 Mid-range speaker, front right
7 Mid-range speaker, rear right
8 Rear power distribution box
9 Rear Electronic Module (REM)
10 Parking maneuvering assistant (PMA)
11 Ultrasonic sensor, rear outer right
12 Ultrasonic sensor, rear center right
13 Ultrasonic sensor, rear center left
14 Ultrasonic sensor, rear outer left
15 Trailer Module (AHM)
16 Headunit basic version (HU-B)
17 Front Electronic Module (FEM)
18 Central information display
19 Center console operating facility
20 Integrated chassis management (ICM)
21 Steering column switch cluster
22 Mid-range speaker, rear left
23 Instrument cluster (KOMBI)
24 Mid-range speaker, front left
25 Dynamic Stability Control (DSC)
26 Ultrasonic sensor, parking maneuvering assistant, left
27 Electromechanical Power Steering (EPS)
28 Reverse gear switch
29 Electronic transmission control (EGS)

The parking maneuvering assistant can be enabled using the park button or by engaging reverse gear. All subsequent operation is then performed via the controller. The longitudinal guidance by the driver monitors the system using the ultrasonic sensors of the Park Assist system (PDC). The Central Information Display (CID) displays the parking operation to the driver continuously. Parking maneuvering assistant is not possible during trailer towing and in sharp bends.

Refer to the Owner's Handbook for restrictions and the display concept!