Anti-tampering method and corresponding circuits and electric systems

An anti-tampering circuit for a vehicle includes an operational circuit providing a predetermined function for the vehicle to be protected, and a control circuit connected to the operational circuit for enabling and disabling operation thereof. The control circuit includes a semiconductor substrate, a communications circuit formed on the semiconductor substrate receiving data corresponding to an identification code from at least one external source within the vehicle, and a non-volatile memory formed on the semiconductor substrate and connected to the communications circuit for storing only once a predetermined identification code. The communications circuit writes the received data to the non-volatile memory as the predetermined identification code when the control circuit is within the vehicle if the predetermined identification code has not already been stored therein. The control circuit further includes a comparator formed on the substrate for comparing the received data with the predetermined identification code and providing a comparison signal. A selector is also formed on the substrate for enabling and disabling the operational circuit responsive to the comparison signal.