COMPUTER FOR ACTIVATING AT LEAST ONE FUNCTION OF A MOTOR VEHICLE

A computer for activating at least one function of a motor vehicle from a portable authentication device, the vehicle including: a plurality of opening elements, a plurality of communication modules, each communication module being mounted in an opening element of the vehicle, a fixed reference module, the computer being configured to: determine the opening position of the at least one opening element detected in the open state, determine an inner detection zone, located in the passenger compartment of the vehicle, and an outer detection zone of the antenna, located outside the vehicle, from the determined opening position, calculate the position of the device, and activate at least one function of the vehicle when the authentication device is located in the inner detection zone of said opening element.