Theory Of Operation
WARNING: This page is about a different car, the 2010 Dodge Charger and 2010 Chrysler 300. However, it is still accessible from the selected car via links, so may be relevant.
The Steering Wheel Control Plus (+) Switch is part of the Right Steering Switch. The switching status is transferred to the Steering Control Module (SCM) by way of the LIN bus, a serial sub-bus. The SCM converts the data to CAN(B) and sends the message to the corresponding module on the bus.