Can't heal fallen comrades, why?

I love playing a medic in planetside, but for the past few months I have been having this issue where I can't revive my fallen comrades. I thought you just point and shoot at the dead body but for some reason it won't work. I can heal comrades that are injured but not ones that are dead. Am I supposed to be pressing another button besides the left mouse button? Is anyone else having this problem? Or am I the only one and I am too dumb to figure this out? Anything will help. Thx.

It was changed some patches back now, left-click to heal, right-click to revive.

Hope that helps.

And now help your comrades getting into battle again, son!

Thank you guys so much, I really appreciate the help.