[JRTJH]

I installed similar motion sensor lights in our fifth wheel. Mine have a "mounting plate that screws to the wall and the "light assembly" snaps onto the mounting plate. On mine, there is a small "indention" on the bottom so you can use a common screwdriver to pry the light off the mounting plate.

Use a mirror and flashlight to view the bottom of the light, you'll probably see that "indention".