Top Causes For Your Security Security Light Not Working

Especially if you live in a more rough part of town, security lights are a godsend. They not only illuminate your property at night when someone (or something) is there, but they can deter thieves. If your security light is not working, there are a few potential causes depending on the symptoms. If the lights stay on, that’s one issue. But if they flicker or won’t turn on, that points to other causes.

The top causes for your security light not working are the lightbulb, a sensor fault or quirk, poor sensor sensitivity, or power problems.

Since that’s a bit of a vague answer, keep reading to learn exactly what you can expect to run into during your troubleshooting.

Security Light Not Working? Check For These Problems

It’s important that you figure out exactly what isn’t working so that you can pinpoint the cause. If your lights stay on, that points to issues with sensors or the protective grid. Otherwise, flickering could be caused by something as simple as an old bulb, or as serious as power supply issues. But if the lights won’t turn on at all? It’s likely that there are either larger problems with your power supply, or that the light itself is busted.

Let’s break that down bit more, shall we?

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Lights Stay On

Breaker box

Theoretically, (depending on the light) upon activation they should be able to sense movement and heat in the surrounding area. This is what is often called the protective grid. The sensors should trip when too many parts of the grid are blocked or detect movement. This means that, in theory, your lights should only be on when there’s clear movement in your property.

If your lights stay on, it could be electrical faults, power surges, user error, or something else. Start by examining your property. Has anything changed since installing? For example, have you added a flag that waves constantly, or has a tree grown into the lights’ range? Look for things that could move with the wind or other weather that might trip your motion sensor.

If nothing seems to be doing so, turn off the light at your breaker for one minute. Have a friend or family member visually ensure that the lights are off, then turn the breaker back on. If the lights stay on and don’t turn off after a few minutes, you may have missed something. Otherwise, it’s likely that there’s an electrical fault in your light. If the light turns off after a few minutes, then you solved the problem! Sometimes it really is as easy as turning it off and back on again.

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If your lights are functioning, but turn on at the slightest sign of movement (such as a tree branch), there’s an easy fix. Adjust your light’s sensitivity or change its direction accordingly, usually with an app or a switch directly on the camera. It’s also good to double-check that the camera has a clear view of what it should – sometimes they get bumped, causing problems.

Lights Flicker

light bulb

If you have multiple lights on the same circuit and one or more is flickering, start by checking their bulbs. A flickering light is more often than not a sign of a dying light bulb – so replace any that flicker and see if that solves the problem. While you’re doing this, ensure they’re all secured tightly, rather than loose.

If this doesn’t solve the problem, you’re going to need to pull out the multimeter or call an electrician. To test your lights, begin by turning off the power at the breaker. Next, go along to every single electrical box in that circuit and test for continuity.

While you’re at it, look for damaged wires, loose connections, or clear damage to the boxes or lights themselves. If there’s clear damage – replace the parts that are damaged or have a pro do it for you. Otherwise, if your lights test as an open circuit, there’s an electrical fault that you’ll definitely need a pro to help with.

Power Problems


This is it, the thing we all fear – issues with your home’s power supply. If you fear this is the problem, first replace the light bulb and test the fixture socket for continuity with your multimeter. If no power is showing up on the meter, it’s a sign that something has gone wrong with your power system.

To test more in-depth, begin by turning the power off at your breaker. Open your electrical box and check each connection to ensure there aren’t any loose wires. If there is a loose connection, remove the connector and ensure it’s the right size for the wires you’re using. If not, replace it.

After this, reattach all wires as securely as you can and give them a slight pull to make sure they’re secured. Additionally, check for continuity with a multimeter as you did with the above solution. If your problems persist, it’s time to have an electrician take a look at your power grid to make sure there aren’t larger underlying problems present.

Other Lights & Your Sensor

This is a deceptively simple solution that may be causing your issues. You see, security lights have a sensor to detect daylight so they don’t turn on when they’re unneeded. But if you have another light facing towards the sensor (or there are street lights), they may be messing with the sensor.

Try moving any other lights you may have around, as well as repositioning the problem light. If this doesn’t work, you can cover the sensor (partially) with electrical tape to prevent other lights from tripping your sensor. This is where awareness of your home and property’s setup comes in handy. If you’ve recently installed a new light or brighter light bulb, that could be the cause of your woes.

Final Thoughts

Security lights are great when they work properly. But when they start flickering or refuse to turn on (or off), it can be a pain to figure out the cause. I always recommend working on the easy fixes first to save yourself time. So start by ensuring your light bulbs are secured and not dead, replacing any that are – especially if they’re flickering. Next, check to make sure nothing on your property has changed recently. Did a tree grow into the sensor’s area, or did you install a new light or flag? These could be tripping your sensor up – so try to reposition them and maybe slightly cover the problem sensor with electrical tape.

The biggest problem that nobody wants is an issue with your power grid, but it’s also a possible culprit. If you’re comfortable using a multimeter, you can test the various places where there could be a fault, and even repair or replace missing or damaged parts of the wiring. Otherwise, as always, please call a professional. They exist to make your life easier and safer – so sit back, make a drink, and let them do their job. It’ll likely save you time and money, and it will be infinitely less frustrating.