Method for initializing and de-initializing a mobile vehicle device suitable for collecting fees of a vehicle , which mobile vehicle device is designed to provide vehicle data (f i ) of the vehicle and/or at least one item of information (b i,j ) dependent on vehicle data (f i ) for wireless transmission, by way of at least one first communication interface of the mobile vehicle device , to at least one registration device, arranged outside the vehicle , of at least one vehicle fee system, comprising: - transmitting the vehicle data (f i ) of the vehicle to the mobile vehicle device , - at least temporarily storing the vehicle data (f i ) in a memory area of a data memory of the mobile vehicle device and - releasably fastening the mobile vehicle device in the vehicle , characterized in that , - in order to transmit the vehicle data (f i ) to the mobile vehicle device , at least one transponder that is fastened on the vehicle outside the mobile vehicle device and that provides the vehicle data (f i ) is activated, and - transmitting the vehicle data (f i ) to the mobile vehicle device comprises reading and receiving the vehicle data (f i ) provided by the transponder by way of a reading apparatus that is included within the mobile vehicle device or is at least temporarily connected thereto in order to exchange data, wherein - i) the transmission of the vehicle data (f i ) of the vehicle to the mobile vehicle device and/or ii) the storage thereof in a memory area of the data memory is triggered as a sufficient condition or is made possible as a necessary but insufficient condition by fastening the mobile vehicle device in the vehicle , and wherein putting the data memory into a state that corresponds to the absence of vehicle data (f i ) in the data memory is triggered as a sufficient condition or is enabled as a necessary but insufficient condition by detaching the mobile vehicle device from the vehicle . - transmitting the vehicle data (f i ) of the vehicle to the mobile vehicle device , - at least temporarily storing the vehicle data (f i ) in a memory area of a data memory of the mobile vehicle device and - releasably fastening the mobile vehicle device in the vehicle , - in order to transmit the vehicle data (f i ) to the mobile vehicle device , at least one transponder that is fastened on the vehicle outside the mobile vehicle device and that provides the vehicle data (f i ) is activated, and - transmitting the vehicle data (f i ) to the mobile vehicle device comprises reading and receiving the vehicle data (f i ) provided by the transponder by way of a reading apparatus that is included within the mobile vehicle device or is at least temporarily connected thereto in order to exchange data, wherein - i) the transmission of the vehicle data (f i ) of the vehicle to the mobile vehicle device and/or ii) the storage thereof in a memory area of the data memory is triggered as a sufficient condition or is made possible as a necessary but insufficient condition by fastening the mobile vehicle device in the vehicle , ii) the storage thereof in a memory area of the data memory is triggered as a sufficient condition or is made possible as a necessary but insufficient condition by fastening the mobile vehicle device in the vehicle , <EOS>