Symptoms: Control panel is locked, and no response or beep when buttons are pressed. A skeleton key icon may be present at the top of the screen.
Resolution: For the current panels that show a house outline in the middle, simply press and hold the Exit button (right arrow) for 3-5 seconds. This will clear the key and unlock the panel.
For the older panels that show the symbols across the bottom, press and hold the UP and DOWN arrows together for 5 seconds, and then release at the same time. This will unlock the panel.
Cause: Most often, this occurs unintentionally, but could be that someone else in the house may have locked the panel so others would not alter settings.