This document presents a secured channel condition estimation algorithm to remove attacks in mobile ad hoc networks (MANETs). The algorithm examines the state of multiple channels and identifies the best channel for routing. It is implemented using Network Simulator 2 (NS2) and evaluated. The results show that the algorithm can accurately estimate channel conditions, identify attacker nodes disrupting routing, and spread alarm messages to avoid routing through attackers. This improves the security and performance of routing in MANETs.