Rocker switch device comprising: a housing; an actuation element attached to the housing; an evaluation unit; and a base plate; wherein the housing is attached to the base plate, wherein the actuation element is movable relative with respect to the housing around at least one rotation axis, and comprises at least two magnets (15l, 15r), wherein at least two magnetic field sensors (13l, 13r) opposite to the magnets (15l, 15r) are coupled at or in the base plate in a stationary manner, which each output a sensor signal (s13r, a13l) depending on a distance (al, ar) between the respective magnetic field sensor (13l, 13r) and the associated magnet (15l, 15r), characterized in that the evaluation unit is configured to evaluate a combination signal of the two sensor signals (s13r, s13l) in order to determine a position and/or a movement of the actuation element based on the combination signal, wherein the combination signal, per position in the movement range of the actuation element relative to the housing, is formed by a value pair that includes the two sensor signals (s13r, s13l); wherein the evaluation unit is configured to compare the combination signal to a validity value range that represents a normal working range of the sensor elements, and to only determine the position and/or the movement of the actuation element when the combination signal is located inside of the validity value range; wherein the evaluation unit is configured to detect, based on the combination signal, an error in form of an external magnetic field and in form of a defect of one of the sensor elements, an exceedance of the temperature range and/or a mechanical defect, wherein an error is present when the combination signal is located outside of the validity value range; wherein the evaluation unit detects an external magnetic field when the two sensor signals (s13r, s13l) are located outside of the validity value range defined by an envelope, and/or wherein the evaluation unit detects the defect of one of the sensor elements or the mechanical defect when the function of the combination signal cannot be represented over the entire movement range. a housing; an actuation element attached to the housing; an evaluation unit; and a base plate; wherein the housing is attached to the base plate, wherein the actuation element is movable relative with respect to the housing around at least one rotation axis, and comprises at least two magnets (15l, 15r), wherein at least two magnetic field sensors (13l, 13r) opposite to the magnets (15l, 15r) are coupled at or in the base plate in a stationary manner, which each output a sensor signal (s13r, a13l) depending on a distance (al, ar) between the respective magnetic field sensor (13l, 13r) and the associated magnet (15l, 15r), characterized in that the evaluation unit is configured to evaluate a combination signal of the two sensor signals (s13r, s13l) in order to determine a position and/or a movement of the actuation element based on the combination signal, wherein the combination signal, per position in the movement range of the actuation element relative to the housing, is formed by a value pair that includes the two sensor signals (s13r, s13l); wherein the evaluation unit is configured to compare the combination signal to a validity value range that represents a normal working range of the sensor elements, and to only determine the position and/or the movement of the actuation element when the combination signal is located inside of the validity value range; wherein the evaluation unit is configured to detect, based on the combination signal, an error in form of an external magnetic field and in form of a defect of one of the sensor elements, an exceedance of the temperature range and/or a mechanical defect, wherein an error is present when the combination signal is located outside of the validity value range; wherein the evaluation unit detects an external magnetic field when the two sensor signals (s13r, s13l) are located outside of the validity value range defined by an envelope, and/or wherein the evaluation unit detects the defect of one of the sensor elements or the mechanical defect when the function of the combination signal cannot be represented over the entire movement range.