Whether they're repelling unwanted visitors or lighting a safe walkway at night, motion sensor lights are a great addition to any outside lighting scheme. But, because they are exposed to the elements 24 hours a day, they can eventually wear down and require replacement. Before you go and put out the money, however, there are a few things you can do to possibly fix the motion sensor without replacing it.

...
Outside light with motion sensor

Troubleshooting the Motion Sensor

Step 1

Look on the bottom of the motion sensor for a button marked "reset." Sometimes in very cold weather, the motion sensor can get frozen in the on position. Pressing the reset button a few times may get it working again. Surges of electricity in the circuit can also cause a motion sensor to stop working properly and this will also cure that problem as well.

Step 2

Spray window cleaner on a clean rag and wipe the lens of the motion sensor. Some sensors are so sensitive, a layer of dust or dirt can cause the lights to kick on earlier than they should. Cleaning the sensor will eliminate that problem.

Step 3

Check the settings on the bottom of the motion sensor to make sure they didn't get changed. If the light isn't staying on as long as it's supposed to or it doesn't turn on until you're right up on it, this may be the reason and a simple adjustment can fix this.

Step 4

Check the circuit breaker if the light isn't coming on at all as it may have tripped. If the circuit is fine, try replacing the light bulbs.

Replacing the Motion Sensor

Step 5

Turn off the power to the circuit. For maximum safety, turn the circuit off at the breaker. Remove the light bulbs from the fixture before taking it apart.

Step 6

Disassemble the light fixture and use the touch-type voltage tester to check for voltage before you disconnect the wires.

Step 7

Disconnect the fixture wires from the feed wires and remove the fixture.

Step 8

Disconnect the motion sensor wires from the fixture wires. Unscrew the motion sensor from the fixture or remove the locknut that's holding it in place and pull the sensor out.

Step 9

Screw the new motion sensor in the same hole you remove the other one. Use the locknut to secure it in place if it requires one.

Step 10

Take the fixture back to the wall box and make the connections. Connect all of the ground wires together with a wire connector. Connect all of the white wires together with a wire connector and wrap electrical tape around the connection. Connect the black wire from the motion sensor to the black wire coming from the wall with a wire connector and wrap electrical tape around the connection. Connect the red from the motion sensor to the black wire coming from the fixture with a wire connector and wrap electrical tape around the connection.

Step 11

Reassemble the fixture and install the light bulbs. Turn the breaker back on and the motion sensor light should be working properly again.

Step 12

Adjust the settings on the new motion sensor for the desired effect.