Automotive electric and electronic (E/E) systems are key drivers for innovation in today's vehicles. While new functions are delivering eco-friendliness (hybrid and pure electric vehicles, etc.), assistance/comfort (drive-by-wire, park-assist, etc.) and active safety (electronic stability control, lane-change-assist, brake-assist, etc.) their inherent complexity is challenging manufacturers and suppliers. At the same time, functional safety of the product is a key issue: During the whole car's product life cycle, there are many potential risks for physical injuries, or even worse, fatalities. Therefore, these potential sources of harm should strictly be avoided. In this work, we focus on a powerful method for verification and validation activities during early phases of the development, namely simulation. Simulation is one of the main methods for verification stated by the functional safety standard ISO 26262. The usage of simulation is primarily targeting requirements on implementation, functional performance and accuracy. For example, simulation is used to conduct back-to-back testing and fault injection. We propose a system level model-based workflow for covering three main aspects during development of safety critical systems: 1) system modeling, 2) system simulation and 3) system verification based on simulation. The workflow is defined in a consistent and seamless way, allowing continuity from preliminary concepts up to the final system verification report.