A micro-electro mechanical system switch includes a fixed electrode formed on a substrate, and a movable electric resistor formed on the substrate, the movable electric resistor serving as an electric resistor that divides an electric potential where the MEMS switch is set to a conduction state. A reproducing apparatus reproduces the manufacturer information to support specific functions. The metal tiles provide an attachment area for at least a portion of one or more wire bonds. The processor is arranged to access the unlock file from the storage location, making it available without requiring connection to the security unit. The shield comprises three metal layers shaped to conform generally to the shape of a high temperature portion of said exhaust system; said metal layers having substantially the same shape and extending in face-to-face adjacency with one layer positioned between the other two layers; all three metal layers being substantially identical. A gate circuit supplies the clock signal to the step-up circuit in accordance with an output signal of the first comparator so that the selected one of the voltages is brought close to the reference voltage.