Motion Sensor Light Doesn’t Turn On

Motion sensor lights are essential safety and security features in most homes and businesses. They illuminate areas where a traditional light switch is either ineffective or not applicable. 

But when they don’t work correctly, they can contribute to falls and security concerns. While there are several reasons they might fail, they don’t always need replacing. Sometimes, they only need minor adjustments to function again.

Today, we’re looking at how these fixtures work and what to do when yours isn’t functioning correctly. 

How do motion sensor lights work?

Whether indoors or out, motion sensor lights are important for safety, security, and energy savings. They’re usually designed to illuminate without the use of light switches. Instead, they work with infrared sensors that detect movement before turning on. 

Some are designed for home exterior use and typically incorporate floodlights with a single sensor. Indoors, they can either be attached to a single light source or tied in with the system for a whole room.

However you use them, they all work under passive, active, or dual infrared motion detectors.

Active sensors

Active sensors send infrared energy waves into a room and then wait for them to return. If they’re not interrupted along their path, the light remains off. When someone enters the space, the sensor detects an interruption and turns on the light, illuminating the area.

These are commonly used in security lights. Because they detect motion instantly, they’re known as radar-based sensors. 

Passive Infrared Sensors (PIR)

Passive infrared sensors don’t send out any waves to detect movement. Instead, they register movement or heat, which signals the light to come on. Essentially, they detect changes in infrared radiation in their field of view to detect changes. 

Unlike cameras, they only detect movement but can’t determine what moved. In principle, all objects have heat energy, and these PIR sensors detect it.

Dual tech sensors

As their name suggests, dual-tech sensors use a combination of active and passive methods to detect movement. Most of them give you the ability to modify how sensitive they are. Because they use two methods, they’re less likely to give false alarms. 

Pets and inanimate objects like ceiling fans won’t cause lights using this technology to come on. 

Troubleshooting your motion sensor light

When your motion sensor light fixture doesn’t come on, there are several points of failure to check. Before you decide to replace your device, walk through these steps. 

Clean out the photocell

Because motion sensors require a clear view to operate properly, a dirty photocell is a problem. Without the ability to detect infrared waves or changes in radiant energy, they’re not functional at all. Cleaning your photocell might be enough to restore functionality to your device. 

Use a wet rag to clean dirt and debris off your sensor and see if that is enough to fix the problem. 

Adjust the sensitivity setting for the motion sensor

Most motion sensors give you the ability to adjust their sensitivity. This provides you with the option of making them pet-safe or simply dialing in the range you want. If it’s not working correctly, take a look at what you’ve got it set to and adjust as needed. You could have it set too low for the coverage area. 

Manually turn your motion sensor light off and on

This is the most straightforward fix for many electronics, and motion sensor lights are no different. Turn it off and back on to see if that resolves the issue. You may need to do it at the circuit panel if you don’t have a switch on the fixture.

Replace your batteries

When you’ve positioned lights for safety and security, you still want them to function as intended. There are plenty of battery-operated devices on the market for a range of applications. If you’ve installed battery-powered motion sensors that stop working, check your power source. Some have a light that lets you know they’ve got a depleted battery, and others don’t.

Your fix could be as simple as replacing your batteries. 

Replace the bulb for your light

If all else fails, check the bulb. While most motion sensors use LED  lights, some still use halogen or incandescent bulbs. Either way, check to see if it’s burned out or damaged. That might be the only change you need to make!

How to reset your motion sensor lights

Occasionally, you may experience a light sensor that either won't go off or stays on for prolonged periods. This is usually a sign that you need to reset your motion sensor lights. 

Check the manual to your light

Always check the manual for your system before attempting to reset using other methods. While most respond to the approach we describe, some need specific treatment. Some need to be disconnected for prolonged periods to reset rather than the quicker methods described below.

Turn off power to the breaker

Most of the time, switching off your unit at the circuit panel is enough to reset the device. Simply identify the correct switch and power down for thirty seconds to a minute. Then turn it back on and see if that fixes the problem.

Reset your motion sensor light through the light switch

Another method for resetting your motion sensor light involves the light switch. Move your switch to the on position and flip it off for two or three seconds. Turn it back on and then check your sensor light. If it’s still not working, you can go through four quick on/off cycles. When the light comes back on, turn it off. Then, wait five to seven seconds before turning it back on. 

Even though there are simple fixes for motion sensor lights, they don’t always solve the problem. Once you’ve tried these methods, if it’s still not working, it might be time to call in the professionals. 

Young Cardinal Electric installs and troubleshoots home lighting!

Putting motion sensor lights around your home can give you peace of mind and a sense of security. Our team at Young Cardinal Electric is ready to install your home lighting system today! And if you’re fighting with the one you already have, we’re here to help. Save yourself a headache and call in a licensed electrician to solve the problem.

Head over to our website to schedule your consultation today!