A/C And Av Switch Assembly Self Diagnosis

Press the BACK and UP switches within 10 seconds after turning the ignition switch from OFF to ACC and hold them for 3 seconds or more.

Fig 1: Locating BACK And UP Switches
Courtesy of NISSAN NORTH AMERICA, INC.
The buzzer sounds, all indicators of the switches illuminate, and the self - diagnosis mode begins.
The ON position continuity of each switch can be checked by pressing the switch. The buzzer sounds if continuity is present.
The self diagnosis mode is canceled when the ignition switch is turned OFF.