Today, embedded systems across industrial domains (e.g., avionics,automotive) are representatives of software-intensive systems with increasingreliance on software and growing complexity. It has become critically importantto verify software in a time, resource and cost effective manner. Furthermore,industrial domains are striving to comply with the requirements of relevantsafety standards. This paper proposes a novel workflow along with tool supportto evaluate robustness of software in model-based development environment,assuming different abstraction levels of representing software. We then showthe effectiveness of our technique, on a brake-by-wire application, byperforming back-to-back fault injection testing between two differentabstraction levels using MODIFI for the Simulink model and GOOFI-2 for thegenerated code running on the target microcontroller. Our proposed method andtool support facilitates not only verifying software during early phases of thedevelopment lifecycle but also fulfilling back-to-back testing requirements of ISO 26262 [1] when using model-based development.