Nikon 1 J5 Reference Manual page 52

Set the clock.
7
Use the multi selector and J button
(0 8) to set the time and date. Note
that the camera uses a 24-hour clock.
s
Press 4 or 2 to highlight time
Press 1 or 3 to highlight daylight
saving time option and press J.
Note: Language and clock can be changed at any time using Language
(0 194) and Time zone and date (0 199) options in setup menu.
30
zone and press J.
Press 1 or 3 to highlight date
format and press J.
Press 4 or 2 to highlight items
and press 1 or 3 to change. Press
J to exit to shooting display when
setup is complete.