Abstract: The on-board network for motor vehicles contains a multiplex control for switching, controlling and monitoring electrical end devices such as switches, operating and indicating elements, sensors and actuators and consists of several bus interfaces (2) coupled to a common bus line (1). The network also includes control devices (4) associated in star configuration via signal lines with the bus interfaces and end devices associated with the control devices. The control devices (4) contain signal converters and a data processor as well as transmitters/receivers for exchanging data signals with the corresponding bus interface. The operation of the on-board network is accomplished in such a manner that the transmission of the data signals from one bus interface to the associated control devices is controlled by the bus interface and follows cyclically the respective control device in the sequence of the groups of inputs and outputs.