A method for activating a vehicle function, by an activation device including a transceiver to communicate with “hands-free” access equipment. The transceiver is equipped with a gyroscope and a magnetometer and two receiving antennas that have a coefficient of electromagnetic coupling between them that is below a threshold. The method includes the following steps for at least two consecutive footsteps: transmission of a signal comprising data of the gyroscope and the magnetometer of the “hands-free” equipment to the vehicle; comparison of the data with representative values of the gyroscope and the magnetometer of the transceiver; determination of a first direction of the user; determination of a second direction of the user based on an estimation of a first angle of arrival of the signal towards the transceiver; comparison of the first direction and the second direction; activation of the vehicle function on the basis of the result of the comparison.