The invention relates to an animal shaped article which is both a stand alone toy and item of wearing apparel comprising a number of removably attachable segments. The method includes a step of carrying out a comparison between the sensor signal and at least one reference signal, repeatedly within a predetermined time interval, in order to obtain a plurality of comparison results, and a step of evaluating the sensor signal based on the plurality of comparison results, in order to detect a fault in the sensor signal. The message may include a graphical representation of the image-forming device that graphically indicates access to the location.