Reliable and predictable operation of power electronics is of increasing importance due to continuously growing penetration of such systems in industrial applications. This article focuses on the fault-tolerant operation of the bidirectional secondary-modulated current-source DC–DC converter. The study analyzes possible topology reconfigurations in case an open- or short-circuit condition occurs in one of the semiconductor devices. In addition, multi-mode operation based on topology-morphing is evaluated to extend the operating range of the case study topology. The influence of post-failure modes on the functionality and performance is analyzed with a 300 W converter prototype. It is demonstrated that failure of one transistor in the current-source side can be mitigated without dramatic loss in the efficiency at maximum power, while preserving bidirectional operation capability.