As automated driving vehicles become more sophisticated and pervasive, it is increasingly important to assure its safety even in the presence of faults. This paper presents a simulation-based fault injection approach (Sabotage) aimed at assessing the safety of automated vehicle functions. In particular, we focus on a case study to forecast fault effects during the modelbased design of a lateral control function. The goal is to determine the acceptable fault detection interval for permanent faults based on the maximum lateral error and steering saturation. In this work, we performed fault injection simulations to derive the most appropriate safety goals, safety requirements, and fault handling strategies at an early concept phase of an ISO 26262-compliant safety assessment process.