Functional description

Depending on the series and bus connection of the steering column switch cluster (SZL), the signals from the shift paddles are transmitted as follows:

• Example F01

  The signals from the shift paddles, representing gearshift commands, are resistance-encoded and transmitted to the steering column switch cluster (SZL) through hard-wired lines. The steering column switch cluster (SZL) converts the signals for the FlexRay.

  The central gateway module (ZGM) is on the FlexRay bus. The task of the central gateway module (ZGM) is to connect all bus systems. This combination allows general use of information from the individual bus systems. The central gateway module (ZGM) is able to implement various reports and speeds on other bus systems.

  The electronic transmission control (EGS) receives the message through a bus signal on the PT-CAN.

• Example F15

  The button signals and thereby the gearshift request are not processed in the steering column switch cluster but only conveyed.

  The signals are transmitted encoded by resistance via direct lines to the Body Domain Controller (BDC). The central gateway module (ZGM) is integrated into the Body Domain Controller (BDC). It is seen as a control unit within the control unit, as the central gateway module (ZGM) acts as a self-sufficient control unit within the Body Domain Controller (BDC). The electronic transmission control (EGS) receives the message through a bus signal on the PT-CAN.

• Example F20

  The button signals and thereby the gearshift request are not processed in the steering column switch cluster but only conveyed.

  The resistance encoded signals are transmitted to the front electronic module (FEM) using direct lines. The central gateway module (ZGM) is integrated in the Front Electronic Module (FEM). It is seen as a control unit within the control unit, as the central gateway module (ZGM) acts as a self-sufficient control unit within the Front Electronic Module (FEM). The electronic transmission control (EGS) receives the message through a bus signal on the PT-CAN.

• Example F25:

  The button signals and thereby the gearshift request are not processed in the steering column switch cluster and in the junction box electronics (JBE) but only conveyed.

  The signals are resistant-encoded and transmitted via direct lines to the electronic transmission control (EGS).

If the rocker switches are used to make a shift in selector-lever position D (D stands for Drive = Automatic transmission), the automatic gearbox switches to manual mode. If no gear is shifted within a time span of 6 seconds or there particularly high acceleration, the automatic gearbox returns to the automatic mode.

Fig 1: Identifying Left/Right Shift Paddle

Courtesy of BMW OF NORTH AMERICA, INC.