A sensor system (100; 200; 300; 400; 500; 600; 700; 800) for providing a main signal (Smain) indicative of a physical signal to be sensed, and an error signal (Serror) indicative of a malfunction of a portion of the sensor system, the sensor system comprising: - a sensor unit (110; 210; 310; 410; 510; 610; 710; 810) configured for providing a sensor signal (SS); - a first signal processor (120; 221; 320; 422; 522; 620; 720; 820) arranged downstream of the sensor unit, and adapted for receiving a second signal (Sx) equal to or derived from a sensor signal (SS), and being adapted for performing a first operation or a first set of operations on said second signal (Sx) so as to provide a first processed signal (PS1); - a second signal processor (130; 231; 330; 432; 532; 630; 730; 830) adapted for receiving the first processed signal (PS1) and for performing a second operation or a second set of operations on the first processed sensor signal (PS1) so as to provide a second processed signal (PS2), wherein the second operation or second set of operations are an inverse of the first operation or of the first set of operations; - and an evaluation unit (140; 240; 340; 440; 540; 640; 740; 840) adapted for receiving the second signal (Sx) or a delayed version (Sx') of the second signal (Sx), and for receiving the second processed signal (PS2), and adapted for evaluating whether the second signal (Sx) or its delayed version (Sx') matches the second processed signal (PS2) within a predefined tolerance margin, and adapted for providing an error signal (Serror) corresponding to the result of the evaluation characterised in that : the second signal processor (130; 231; 330; 432; 532; 630; 730; 830) has at least one characteristic selected from the group consisting of: being at least 2.0 times slower, being less precise, having a signal-to-noise ratio of at least 10 dB lower, occupying less than 50% of the space, than the first signal processor (120; 221; 320; 422; 522; 620; 720; 820). - a sensor unit (110; 210; 310; 410; 510; 610; 710; 810) configured for providing a sensor signal (SS); - a first signal processor (120; 221; 320; 422; 522; 620; 720; 820) arranged downstream of the sensor unit, and adapted for receiving a second signal (Sx) equal to or derived from a sensor signal (SS), and being adapted for performing a first operation or a first set of operations on said second signal (Sx) so as to provide a first processed signal (PS1); - a second signal processor (130; 231; 330; 432; 532; 630; 730; 830) adapted for receiving the first processed signal (PS1) and for performing a second operation or a second set of operations on the first processed sensor signal (PS1) so as to provide a second processed signal (PS2), wherein the second operation or second set of operations are an inverse of the first operation or of the first set of operations; - and an evaluation unit (140; 240; 340; 440; 540; 640; 740; 840) adapted for receiving the second signal (Sx) or a delayed version (Sx') of the second signal (Sx), and for receiving the second processed signal (PS2), and adapted for evaluating whether the second signal (Sx) or its delayed version (Sx') matches the second processed signal (PS2) within a predefined tolerance margin, and adapted for providing an error signal (Serror) corresponding to the result of the evaluation characterised in that : the second signal processor (130; 231; 330; 432; 532; 630; 730; 830) has at least one characteristic selected from the group consisting of: being at least 2.0 times slower, being less precise, having a signal-to-noise ratio of at least 10 dB lower, occupying less than 50% of the space, than the first signal processor (120; 221; 320; 422; 522; 620; 720; 820). <EOS>