The automotive industry is currently undergoing a paradigm shift from federated electronic control unit structures to centralized zonal architectures, necessitating a radical re-evaluation of functional safety and fault tolerance. As vehicles transition toward higher levels of autonomy, the reliability of the underlying computational substrate becomes the primary determinant of system integrity. This research provides an exhaustive analysis of fault-tolerant regimes, specifically focusing on the integration of dual-core lockstep architectures and advanced voting strategies within automotive zonal controllers. By synthesizing classical redundancy theories with modern hardware implementations such as the NXP S32G processor, this study establishes a unified taxonomy for fail-operational, fail-degraded, and fail-safe behaviors. We examine the theoretical implications of time and space redundancy, the evolution of software-implemented fault tolerance, and the formalization of safety arguments through structured methodologies. The article further explores the complexities of diverse programming and n-modular redundancy in high-interference nanometer technologies. The findings suggest that a multi-layered approach-combining hardware-level lockstepping with software-defined voting logic-is essential to mitigate common-cause failures and transient soft errors. This comprehensive framework serves as a publication-ready blueprint for the next generation of safety-critical embedded systems, ensuring compliance with ISO 26262 standards while addressing the limitations of traditional fault-management strategies.