Vibration actuator in the steering wheel

The vibration actuator is fitted in the spoke of the steering wheel. The vibration actuator has the task of causing the steering wheel to vibrate. The lane departure warning and lane change warning assist systems use these vibrations to warn the driver of a hazardous situation.

The steering wheel module also housed inside the steering wheel activates the vibration actuator. The request for activation of the vibration actuator is sent by the Integrated Chassis Management (ICM) or the Dynamic Stability Control (DSC) as a bus signal to the bus users.

• Vehicles with Body Domain Controller

  The Body Domain Controller (BDC) forwards this request across the LIN bus to the steering wheel module in the steering column switch cluster.

• Vehicles with Front Electronic Module:

  The Front Electronic Module (FEM) forwards this request via LIN bus to the steering wheel electronics in the steering-column switch cluster.

• Vehicles with junction box electronics:

  The junction box electronics (JBE) forward this request via the LIN bus to the steering wheel electronics in the steering-column switch cluster.

The steering column switch cluster is not a control unit.

Fig 1: Identifying Electronic Steering Wheel Module And Vibration Actuator

Courtesy of BMW OF NORTH AMERICA, INC.