Don't know what kind of transmission you have, but it is supposed to work this way:
1. With vehicle running, trunk release under dash or key fob works if car is stationary and the auto trans is in P (I would suspect man trans would require parking brake engaged). Trunk lid switch works if interior lock button is used to unlock car.
2. With vehicle off, under dash works with vehicle in P. Trunk lid release works only if vehicle is unlocked with interior lock button. Key fob always works.
This is my experience with the thing anyway.