Starting The Self-Diagnosis Mode

WARNING: This page is about a different car, the 2003 Nissan Murano. However, it is still accessible from the selected car via links, so may be relevant.

Turn ignition switch from OFF to ACC.
Within 10 seconds press and hold the switches "PAUSE/MUTE" and "PREV" simultaneously for 3 seconds.

Then the self-diagnosis operates.

Fig 1: Identifying "PAUSE/MUTE" And "PREV" Switches

Courtesy of NISSAN MOTOR CO., U.S.A.