As capacitive Erfassungselekrode operated heating element

A seat heater and capacitive occupancy sensor in a combination comprising a heating network including a heating element (11) and a capacitive sensing circuit, which is connected to the heating element to sense a capacitive load. There are a first and a second interface for connecting the heating element to a first or second terminal of a power source is provided. Each interface includes electronically controlled switch (3, 5; 4, 6) which are arranged in series and an intermediate node (20; 21) define. An oscillator (8) is AC coupled to the intermediate node, for applying an oscillating voltage to these. A current measuring means (9), which is AC-coupled between the oscillator and the heating element, the alternating current potential of the heating element keeping in amplitude and phase of at least substantially equal to the oscillating voltage to the intermediate nodes and derives the capacitive load in a resulting current flowing in the heating element flows.