Hazard and Horn Reminder
WARNING: This page is about a different car, the 2008 Nissan Maxima. However, it is still accessible from the selected car via links, so may be relevant.
When doors are locked or unlocked by a door request switch, Intelligent Key unit sends hazard request signal to BCM via CAN communication line. BCM flashes hazard warning lamps as a reminder. Intelligent Key unit sends a chirp signal to the Intelligent Key warning buzzer (engine room) as a reminder. The hazard and buzzer reminder has a horn chirp mode (C mode) and a non-horn chirp mode (S mode).