A security light illuminates when its built-in motion sensor detects movement within a given area it is aimed toward. You can replace a malfunctioning sensor on a security light so that the security light can continue being used. A few household tools will be needed, as will a replacement motion sensor that can be acquired from an electronics store or, in some cases, the same hardware store or home and garden shop where you originally purchased the security light.
Things You'll Need
Phillips jeweler’s screwdriver
#15 Torx screwdriver
Flat-edged jeweler's screwdriver
Disconnect the power line feeding electricity to the security light. This involves tripping the appropriate circuit breaker in a fuse box if the security light is hard-wired to its power supply or pulling its power cord from a wall outlet if the security light is an indoor, portable model.
Remove the security light's front panel using a Phillips jeweler's screwdriver or a Torx screwdriver, depending on the manufacturer. Pull the front panel off slowly so the wires connecting the motion sensor inside the front panel are not broken off from the circuit board inside the security light.
Loosen the two screws that the black and red wires attached to the motion sensor are wrapped around, using a Phillips jeweler's screwdriver . Unwind the wires. If the wires are wrapped around a black and red wire connected to the circuit board instead, unwrap the electrical tape holding the wires together and separate them.
Insert the tip of a flat-edged jeweler's screwdriver beneath the motion sensor on one side and lift. Repeat this on the other side of the motion sensor. Pull the motion sensor out from the slot in the front panel. Dispose of the motion sensor properly since it is an electronic part.
Strip a half inch of insulation off the ends of the two wires attached to the replacement motion sensor, using wire strippers.
Wind the exposed end of the black wire around the screw where the original sensor's black wire was. Repeat this procedure with the exposed end of the red wire attached to the replacement motion sensor. Tighten the screws. If the wires were wrapped around wires connected to the circuit board instead, wrap the exposed end of the black wire from the sensor around the black wire from the circuit board and the exposed end of the red wire from the sensor around the red wire from the circuit board. Wrap each set of wires with a strip of electrical tape.
Apply bonding glue to the edges of the slot on the inside of the front panel. Place the replacement motion sensor in the slot. Press the sensor against the slot and hold it there for a minute to let the glue take hold. Let the bonding glue set for an hour before continuing.
Place the front panel back on the security light. Reattach the screws. Return electrical power to the security light.