Abstract: An apparatus is provided for secured communication between control units in a vehicle (20). The control units have at least one communication interface (IT1) connected to a first part of a wired vehicle bus system (B1) for exchanging messages. At least one secured control unit (CU4, CU5) is connected to the vehicle bus system (B1), wherein the secured control unit (CU4, CU5) has at least one further communication interface (IT2), to which a separate part of the vehicle bus system (B1?) is connected. The secured control unit (CU4, CU5) has a gateway function (GWF) and security equipment (SE) which fulfills at least the function of a firewall (FW) that is used to ward off attacks on one of the control units in the separate part of the vehicle bus system (B1?) from the first part of the vehicle bus system (B1).

Abstract: A method is for activating a vehicle function, wherein a controller for activating the vehicle function checks an access authorization of the mobile device and activates the vehicle function only if the authorization is acceptable. The method includes: a) the controller sending a request to the mobile device demanding transmission of the authorization for a vehicle function, b) the mobile device receiving the request from the controller and sending the authorization to the controller, c) the controller checking the authorization and activates the vehicle function if the authorization is acceptable, d) the mobile device sending the authorization only if the device was previously actuated for the purpose of authorization and thus was authorized to send the authorization, e) and the controller activating the vehicle function only if a signal of a sensor device actuatable by the user has previously been received by the controller.