Wireless sensor network (WSN) should be designed such that it is able to identify the faulty nodes, rectify the faults, identify compromised nodes from various security threats, and transmit the sensed data securely to the sink node under faulty conditions. In this paper, we propose an idea of integrating fault tolerance and secured routing mechanism in WSN named as fault tolerant secured routing: an integrated approach (FASRI) that establishes secured routes from source to sink node even under faulty node conditions. Faulty nodes are identified using battery power and interference models. Trustworthy nodes (non-compromised) among fault-free nodes are identified by using agent-based trust model. Finally, the data are securely routed through fault-free non-compromised nodes to sink. Performance evaluation through simulation is carried out for packet delivery ratio, hit rate, computation overhead, communication overhead, compromised node detection ratio, end-to-end delay, memory overhead, and agent overhead. We compared simulation results of FASRI with three schemes, namely multi-version multi-path (MVMP), intrusion/fault tolerant routing protocol (IFRP) in WSN, and active node-based fault tolerance using battery power and interference model (AFTBI) for various measures and found that there is a performance improvement in FASRI compared with MVMP, IFRP, and AFTBI. IFRP, intrusion/fault tolerant routing protocol; INSENS, intrusion-tolerant routing protocol for wireless sensor networks; MVMP, multi-version multi-path; FDWSN, fault detection of wireless sensor networks; BTRM-WSN, bio-inspired trust and reputation model in wireless sensor network; LSRP, link state routing protocol; AFTBI, active node-based fault tolerance using battery power and interference model; FASRI, fault tolerant secured routing: an integrated approach; CDR, compromised node detection ratio.