Purchase a motion sensor for your specific light and read the instructions. Motion sensors are not universal, and if you have an exterior flood light you want to make motion activated, you’ll need to buy the attachment from the same company that made your light.[5] Otherwise, you’ll need new wiring to run a separate line for the motion sensor, which will require an electrician.[6]
You also need a gasket or opening on the fixture to attach your motion sensor to. If there isn’t a small opening or cover on the outside of the fixture, your light cannot be converted to a motion-activated light without totally installing a new fixture with a built-in motion sensor.
2
Flip the breaker to turn power to the light off. Go to your fuse box and flip the circuit breaker for the light you’re going to install the motion sensor on. If you can’t figure out which circuit is attached to your light, just flip the main off. This is mandatory, since you must ensure that there’s no electrical signal running to your light.[7]
Test the light with a multimeter or flip the light on and off to ensure that there’s no electricity running to it.
3
Unscrew your fixture or remove the cover to expose the wiring. Look at the fixture to see how it’s attached to the electrical box behind it. Use a screwdriver or hex key to unscrew the fixture from the wall. If there are no screws at all, you can typically pop the cover off. Gently pull the fixture off of the wall and let it hang loosely by the wires.[8]
At this point, it’s best to take a photo of your wiring setup. If you aren’t successful in installing the motion sensor or you need a reminder of which wire connects to what, you’ll be glad you have a reminder!
4
Remove the cover on the gasket for the motion sensor. This is going to vary from fixture to fixture. The slot on your fixture for the motion sensor is usually going to be covered by something. If there’s a screw-shaped cover, use a screwdriver to remove it. If it’s just a flat cap, you can typically pry it off with a flathead screwdriver or by hand.[9]
If you don’t have a gasket to attach the light to, you’ll need to hire an electrician to install a brand-new light.
