A customer terminal of a “self-scanning shopping” system, which is configured to store at least one shopping session in a non volatile memory, includes a main processor, a product code reader, a location for non volatile storage of an open shopping session indicator and/or an identifier, either direct or indirect, of a shopping session, and a supervisor circuit. In a working operating state, the main processor periodically sends a heartbeat to the supervisor circuit. The supervisor circuit commands a reset of the main processor when, from the lack of receipt of the heartbeat, it detects a non working operating state of the main processor. The main processor, upon reset, checks whether there is an open shopping session based on the contents of said memory location and in the affirmative case restores said shopping session.