The automotive industry is currently going through rapid changes from a mechanical industry to one driven by innovation in electronics and embedded software. This significant change creates also significant challenges to the industry. One of the most important is the ability to create safe vehicles, emphasizing the importance of safety by design. This paper is intended to contribute to current activities working towards an industry-wide development of reliable and secure systems. Correct by design methodology, including formal methods, have the potential to improve dependability of systems in this domain. And their use at an early stage of the development process ensures faster time to market. In this paper, we present tool support for our approach that aims at integrating the formal analysis and verification of functional requirements from early stages of the development life cycle, by using model checking technique. From informal requirement specifications the tool delivers models. They will be used to produce evidences that the requirement specifications are realizable, otherwise it can guide their revision. The approach is illustrated by a case study based on a specific function of autonomous vehicles.