Nikon D5500 - Manual (Page 291)

267 A Custom Settings: Fine-Tuning Camera Settings
Choose the role played by the A (L)
button.
f2: Assign AE-L/AF-L Button
G button
➜ A Custom Settings menu
Option Description
B AE/AF lock
Focus and exposure lock while the A (L) button
is pressed.
C AE lock only Exposure locks while the A (L) button is pressed.
E
AE lock
(Hold)
Exposure locks when the A (L) button is
pressed, and remains locked until the button is
pressed a second time or the standby timer
expires.
F AF lock only Focus locks while the A (L) button is pressed.
A AF-ON
The A (L) button initiates autofocus. The
shutter-release button can not be used to focus.
A (L) button