Nikon D5500 - A3: Built-In AF-Assist Illuminator

250 A Custom Settings: Fine-Tuning Camera Settings
Choose whether the built-in AF-assist
illuminator lights to assist the focus
operation when lighting is poor.
a3: Built-in AF-assist Illuminator
G button ➜ A Custom Settings menu
Option Description
On
The AF-assist illuminator lights when lighting is poor (for
more information, see page 352).
Off
The AF-assist illuminator does not light to assist the focus
operation.
The camera may not be able to focus using
autofocus when lighting is poor.
AF-assist illuminator