Driving Dynamics Switch: Notes

The driving dynamics switch and DTC button are integral components of the center console operator control unit.

Fig 1: Identifying Driving Dynamics Switch And DTC Button Installation Location

Courtesy of BMW OF NORTH AMERICA, INC.

The new driving dynamics switch consists of two buttons labeled "COMFORT" and "SPORT". This is a rocker switch that returns automatically to the center position after it is pressed. The center position corresponds to the "no button pressed" status.

Both buttons of the driving dynamics driving switch are connected directly to the ICM control unit via two lines. The ICM control unit applies a voltage at these lines. Both buttons are connected to the ground via a resistance network. The ICM control unit can determine the following by back-scanning the voltage obtained:

• whether a button has been pressed and, if so, which of the two buttons,
• whether breaks in the wiring exist and
• whether a short to ground has occurred.

In previous vehicles, the familiar DTC button is connected electrically, e. g. to the IHKA control unit (E70/E71). In the F01/F02 on the other hand, the DTC button is connected to the ICM control unit via an electrical wire. A voltage is applied to this wire by the ICM control unit. The DTC button connects to the ground. The ICM control unit can determine by means of voltage measurement whether the DTC button is operated.

The "Driving dynamics control" function in the ICM control unit evaluates the operation of the driving dynamics switch and DTC button and uses this as the basis for determining the corresponding mode ("see FUNCTIONS " section). The ICM control unit sends signals via the bus system to inform the driver at the instrument cluster which mode has been set.

The footwell module supplies power to the center console operator control unit via terminal 58g for the locating lamp.