WARNING: This page is about a different car, the 2012 Nissan Altima. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Intelligent Key System/Engine Start Function Component Parts Location (1 Of 2)
Courtesy of NISSAN NORTH AMERICA, INC.
Fig 2: Intelligent Key System/Engine Start Function Component Parts Location (2 Of 2)