Method and apparatus for detecting the operating state of an internal combustion engine

The invention relates to a method for detecting the operating state of an internal combustion engine and an apparatus corresponding thereto. According to the invention from the time profile (1) is proposed to derive the electrical voltage of the electrical system of a motor vehicle the operating state of the motor vehicle which drives the internal combustion engine. The inventive method is suitable for automatic switching on and off electrical loads, the retrofitted switched in operation, and should be turned off in the idle state of the vehicle in a motor vehicle, such. As navigation systems, driver assistance systems, and especially automatic toll collection systems.