Channel Check Diagnostics
WARNING: This page is about a different car, the 2007 Nissan Sentra. However, it is still accessible from the selected car via links, so may be relevant.
When all segments are illuminated, press the "TUNE" down switch to enter channel check diagnostics. The self-diagnostic function will then send a tone to each channel (FL, RL, RR, FR) for 1 second.