WARNING: This page is about a different car, the 2004 Nissan Titan. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Wiring Diagram - Audio Base System AV-AUDIO-01 (1 Of 2)
Courtesy of NISSAN MOTOR CO., U.S.A.
Fig 2: Wiring Diagram - Audio Base System AV-AUDIO-02 (2 Of 2)