Abstract: A control device includes an elongated mechanical transmission member (10; 110) interposed between the gearbox and a control member (100) for transmitting to the gearbox the commands imparted through the control member, in such a manner that the gear engaged by means of the gearbox is linked to the linear position of the transmission member (10; 110). The device is provided with a position sensor (26; 126) including a movable reference element (28; 128), the movement of which is univocally determined by the movement of a rigid end portion (14; 114) of the transmission member (10; 110), and a stationary detection element (30) for detecting the position of the reference element (28; 128).