Board Thread:Versus Debates/@comment-26005711-20160614093346/@comment-3965545-20160615215154

Madara's chakra was too low to turn his Sharingan on when Hashirama shanked him lol therefore I think maybe chakra levels effect the sensory ability.. as Sasuke can only sense Naruto thanks to them being transmigrants and Naruto having such massive chakra levels thanks to Kurama.