SIGNAL TRANSMISSION METHOD AND APPARATUS

摘要

In a method and apparatus for transmitting signals from a control device to a diagnostic device in a motor vehicle, a transmission of signals in a serial form is obtained by means of an electric current. In order to detect whether the diagnostic device is connected to the control device a voltage is measured in a diagnostic signal-conducting lead connected to the diagnostic device. This voltage is varied by means of a resistor mounted at the input of the diagnostic device when the diagnostic device is connected to the control device.