Today's vehicles contain hundreds of circuits, sensors, and many other electrical components. Communication is needed among the many circuits and functions of the vehicle. For example, when the driver presses the headlights switch on the dashboard, the headlights react. For this to occur, communication is needed between the dashboard switch and the front of the vehicle.
In current vehicle systems this type of communication is handled via a dedicated wire through point-to-point connections. If all possible combinations of switches, sensors, motors, and other electrical devices in fully featured vehicles are accumulated, the resulting number of connections and dedicated wiring is enormous. Networking provides a more efficient method for today's complex in-vehicle communications.
In-vehicle networking, also known as multiplexing, is a method for transferring data among distributed electronic modules via a serial data bus. Without serial networking, inter-module communication requires dedicated, point-to-point wiring resulting in bulky, expensive, complex, and difficult to install wiring harnesses.