A system for transmitting transmissions in vehicles includes a first communication module for establishing a communication connection to a communication terminal of a supplier, which communication terminal receives authorization data by a communication network, a first identification routine for uniquely identifying a supplier, a second communication module for establishing a communication connection to a communication device of a control unit of the access assembly of a vehicle by wireless communication network, a second identification routine for uniquely identifying the system by the access assembly, a third communication module for receiving update request information of the driver, and an update routine for updating authorization data in a memory of the system.