Abstract: A system for testing functionalities of a vehicle while driving the vehicle having a message-based bus network topology comprises a software server configured to be connected to the bus and to take vehicle sub-system information therefrom and interpret it as output from a timed automaton. The system also comprises at least one client in the form of an executable test script written in a programming language and configured to from the server subscribe specific vehicle sub-system information to be used by a test assessment oracle of the test script for assessing a particular function or sub-function of the vehicle.