A method of making a “zero knowledge” connection between a computer (2) and an electronic unit (5). At the start of the method, the configuration unit (1) is connected with the computer (2), and a web server is initiated in the configuration unit (1) via the trusted execution environment. A secure network connection is made to a server (3) by the configuration unit (1) and, via the network connection, the items of information required for connection with the electronic units, to which a connection can be made, are synchronized with the trusted execution environment. After synchronization occurs, an electronic unit (5) is selected by the web server via an input of the computer (2), to which electronic unit (5) a connection is made via the trusted execution environment using the stored, synchronized items of information, and via the web server prescribed menu-driven maintenance or configuration steps can be executed.