A symmetrical blocking transient voltage suppressing circuit for suppressing a transient voltage includes an NPN transistor having a base electrically connected to a common source of two transistors whereby the base is tied to a terminal of a low potential in either a positive or a negative voltage transient. A rubber elastic body including lubricant is provided between an outer circumference of an inner casing having a roughly cross shape in section and an inner circumference of an outer casing while the outer casing and the rubber elastic body are enabled to slide in their axis direction so as to absorb a shake in the axis direction from a steering gear box side. The method and system may optionally include undertaking an action to change at least one of the indicator of access ability and the indicator relating to authorization.