The chapter proposes a novel self-healing fault accommodation framework for nonlinear fully actuated system (FASs) under faulty sensors. Beginning from a nonlinear FAS model with multiple measurements, a d-redundant observability proposition is derived from the observable structure under each sensor measurement. Since the error dynamics is ultimately uniformly bounded, a definition of ideal sensor fault tolerance is determined. After a necessary and sufficient fault-tolerance condition is developed, a self-healing fault-tolerant control framework is proposed, which can cope with sensor faults during steady-state or transient processes. The main results are proved theoretically and illustrated experimentally.