If the FRITZ!Box loses power, all of the settings of the LED light FRITZ!DECT 500 for brightness and color are retained. The LED light remains on or off, depending on its state at the time when the FRITZ!Box lost power. Automatic switching of the LED light, for example switching schedules, will not function and routines also cannot be switched. As soon as power is restored to the FRITZ!Box, switching will function again. If you configured a specific switching state for the LED light after a power failure on the "Light setting" tab in the menu "Smart Home > Device Management" or "Devices and Groups" of the user interface of your FRITZ!Box, this switching state will be activated after the restart.

If there is no internet connection, the LED light can still be switched within the home network. However, a functioning FRITZ!Box with an internet connection and an existing connection to the LED light are prerequisites for smooth and correct operation.