How to Install Exterior Motion Sensor Lights

Lighting your home's exterior serves two purposes: convenience and security. Motion sensor lights remove the need to fumble for keys in the dark and discourage unwanted visitors by eliminating the shadows they prefer. When done well, the sensor is calibrated to catch motion from the driveway or walkway without triggering every time a stray cat wanders by or the wind rustles a nearby bush. Installing these fixtures is a straightforward electrical project, provided you respect the power. You are essentially swapping a static light for an intelligent one. The key to a professional-looking installation is ensuring the mounting base is perfectly sealed against the house siding to prevent water intrusion, which is the leading cause of premature sensor failure.

Kill the Power First. Locate your home's electrical service panel and flip the circuit breaker associated with the exterior light. Use a non-contact voltage tester on the existing fixture to confirm no power is reaching the wires before proceeding.
Document Before Dismantling. Unscrew the existing light fixture from the mounting plate or siding. Carefully disconnect the wire nuts, untwist the wires, and set the old fixture aside.
Level and Secure Bracket. Secure the manufacturer-provided mounting bracket to the junction box using the provided machine screws. Ensure the bracket is level and centered over the box.
Match Colors, Test Tight. Match the wires from the light to the house wires: black to black (hot), white to white (neutral), and the bare or green copper wire to the grounding screw or green wire. Secure each connection with a fresh wire nut and wrap them with electrical tape for extra security.
Seal and Secure Fixture. Gently tuck the wires back into the junction box, taking care not to pinch them. Align the new fixture with the mounting bracket and secure it using the included decorative nuts or screws.
Dial In the Sensitivity. Restore power at the breaker and turn on the wall switch. Use the adjustment dials on the bottom of the sensor to set the sensitivity and the duration the light stays on after movement stops.