An apparatus for locking and/or unlocking, for an access and/or drive authorization in a motor vehicle of a keyless entry/go functionality, for a wireless remote control of a first device in the motor vehicle and an associated second device designed as an electronic key, an ID-transponder or a chip card, with both devices for the intended operation having transmitters and/or receivers for electromagnetic signals which allows a large operation distance and a long battery lifetime of the second device. The first device transmits a first cyclic repeated signal for the activation and/or authentication of the second device with a first data protocol within a first transmission time interval and with a first cycle time.