The Kraftfahrt-Bundesamt (KBA) carries out targeted analyses of the engine control software of vehicles in addition to emission tests on exhaust gas roller test benches and in real road traffic. For this purpose, the SW documentation and specifications of the engine control system are passed on to KBA by the respective vehicle manufacturer. KBA software analysts are specifically investigating these with regard to possible defeat devices. In combination with emission tests to be carried out on the basis of the software test, the admissibility or inadmissibility of the defeat devices can be assessed.