A sensor device for a motor vehicle including a control and evaluation circuit and at least one sensor electrode coupled therewith, wherein the sensor electrode is designed as a conductor loop, which is coupled to the control and evaluation circuit at two contacts. The control and evaluation circuit has a measurement circuit, which monitors the sensor electrode for capacitance changes. The control and evaluation circuit includes a testing circuit that can be activated intermittently, which tests the integrity of the sensor electrode and its coupling to the control and evaluation circuit. The testing circuit has a triggering mechanism that can be activated in order to intermittently couple a test capacitor to the sensor electrode, such that the measurement circuit also detects the capacitance of the test capacitor in addition to the capacitance of the sensor electrode.