2008 Nissan Altima Owner's Manual - Page 146

The hazard warning lights will flash once and the horn will sound once to confirm that the horn beep feature has been reactivated. Deactivating the horn beep feature does not silence the horn if the alarm is triggered. WARNING SIGNALS To help prevent the vehicle from moving unexpectedly by erroneous operation of the Intelligent Key or to help prevent the vehicle from being stolen, a chime or buzzer sounds from inside and outside the vehicle and a warning is displayed in the instrument panel. WPD0361 WPD0362 Using the panic alarm If you are near your vehicle and feel threatened, you may activate the panic alarm to call attention button on the by pushing and holding the Intelligent Key for longer than 0.5 second. The panic alarm and headlights will stay on for 25 seconds. The panic alarm stops when: ● it has run for 25 seconds, or ● any button is pushed on the Intelligent Key. Silencing the horn beep feature If desired, the horn beep feature can be deactivated using the Intelligent Key. To deactivate: Press and hold the and buttons for at least 2 seconds. The hazard warning lights will flash three times to confirm that the horn beep feature has been deactivated. To activate: Press and hold the and buttons for at least 2 seconds once more. When a chime or beep sounds or a warning is displayed, be sure to check the vehicle and the Intelligent Key. See the troubleshooting guide that follows and "Vehicle information display indicator lights and warnings" in the "Instruments and controls" section. TROUBLESHOOTING GUIDE Verify the location of all Intelligent Keys that are programmed for the vehicle. If another Intelligent Key is in range or inside the vehicle, the vehicle system may respond differently than expected. 3-14 Pre-driving checks and adjustments