Quick Answer –
Should Both Garage Door Safety Sensors Be Green?
No, both garage door sensors should not be green.
- Only the receiver sensor should display a solid green light, which means it is properly aligned and receiving the signal.
- The transmitter sensor typically shows an amber/orange/red light or may not have a light at all, depending on the brand or model.
- A blinking or unlit green sensor usually indicates a misalignment, blockage, wiring issue, or sensor failure.
- Both sensors must be aligned and unobstructed to allow the garage door to close safely.
- Never bypass or disable sensors—they are part of the UL 325 safety standard and exist to prevent injury and damage.
If your garage door won’t close or one of the sensor lights is off, it’s time to troubleshoot or call a professional.
Want a deeper dive into how garage door safety sensors were developed, how they work, and why they matter?
Read our full overview here:
Understanding the History and Purpose of Garage Door Safety Sensors
What Garage Door Sensors Do —
And Why They Matter
Garage door sensors are a built-in safety feature required on all garage doors manufactured since 1993, according to UL 325 safety regulations. Their primary role is to prevent the garage door from closing on people, pets, vehicles, or other objects.
These sensors work in pairs:
- One is a transmitter, which sends an invisible infrared beam.
- The other is a receiver, which detects that beam.
If anything breaks the beam while the door is closing, the opener automatically reverses the door’s direction to prevent harm or damage.
What the Sensor Lights Mean
Understanding the lights on your sensors can help you diagnose problems quickly. Here’s what typical sensor lights mean:
- Transmitter Sensor: Amber/orange/red or no light – actively sending the beam.
- Receiver Sensor:
- Solid green – beam received, sensors aligned correctly.
- Blinking or off – misalignment, obstruction, or wiring issue.
Common Causes of Garage Door Sensor Light Issues
1. Sensor Misalignment
The most common issue is that one of the sensors has been bumped or knocked out of alignment. Sensors must be facing each other directly to communicate.
2. Dirt or Debris
Dust, cobwebs, or insect nests can interfere with the infrared beam. Even a thin layer of grime can block the signal.
3. Sunlight Interference
In some garages, direct sunlight can interfere with the signal from the transmitter to the receiver. This issue is more common in afternoon-facing garage doors.
4. Wiring Problems
Loose or damaged wires can disrupt power or communication between the opener and the sensors.
5. Sensor Failure
Over time, sensors can fail due to age, exposure to moisture, or internal damage. If the green light won’t come on even after cleaning and realigning, the sensor may need to be replaced.
How to Troubleshoot Garage Door Sensor Lights
If your garage door isn’t closing and you suspect a sensor issue, here are a few DIY steps to try before calling a professional:
Step-by-Step Troubleshooting:
- Check the lights on both sensors.
- Gently clean the lenses with a dry, soft cloth.
- Ensure both sensors are mounted at the same height and pointing directly at each other.
- Adjust the receiver sensor slowly until the green light becomes steady.
- Check the wiring at the back of both sensors.
- Look for sunlight or reflective surfaces that could interfere with the beam.
If the green light won’t remain steady after these steps, it may be time to replace one or both sensors.
Why the Green Light Is So Important
The green light on the receiver sensor is your visual confirmation that the safety system is aligned and working properly. If that light is blinking, it means the infrared beam is not being received—which tells the opener to stop or reverse the door’s movement.
Garage door openers are intentionally programmed to refuse to close the door when there’s a safety sensor failure. This isn’t a glitch—it’s a built-in protection feature to keep you and your family safe.
Important Safety Warning ⚠️
Never bypass or disable your garage door safety sensors.
We understand how frustrating it can be when your garage door won’t close. But disconnecting or taping over the sensors to “get it working again” is not only unsafe—it’s a violation of federal safety law.
According to UL 325, a nationally recognized safety standard enforced under the Consumer Product Safety Improvement Act, all residential garage door openers manufactured after January 1, 1993, must include an entrapment protection system—such as photoelectric safety sensors. These sensors are required to be functional, aligned, and actively monitored.
If you disable or bypass them, you are:
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Violating federal safety standards.
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Creating a serious safety hazard.
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Risking personal liability for injuries or property damage.
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Likely voiding your manufacturer’s warranty.
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Rendering your garage door system non-compliant and potentially inoperable.
Many homeowners make the mistake of bypassing safety sensors due to:
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Misalignment or dirt buildup.
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Frustration with a non-working door.
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Unawareness that these sensors are not optional—they’re legally required.
Please don’t take the risk.
If the green sensor light is off, blinking, or the door won’t close properly, the safe and legal solution is to call a professional garage door technician.
At Overhead Door Company of Huntsville/North Alabama™, our technicians are trained to restore sensor alignment, diagnose wiring issues, or replace faulty sensors—all in compliance with UL 325. Your safety is our top priority.
Legal Risk & Insurance: What You Should Know ⚠️
Yes—injuries caused by malfunctioning or bypassed garage door sensors have led to serious lawsuits.
In several documented cases, courts have held homeowners, installers, and manufacturers legally responsible when required safety features—such as photoelectric safety sensors—failed or were improperly disabled. These cases have involved personal injury, wrongful death, and claims of negligence due to non-compliance with federal safety standards, particularly UL 325.
If someone is injured because your garage door fails to stop or reverse, and it’s discovered that the safety sensors were:
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Disconnected
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Misaligned and unaddressed
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Bypassed intentionally
You could be held liable—even if the injury occurred accidentally.
Does Homeowners Insurance Cover Injuries from Faulty Sensors? ⚠️
It depends.
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Most standard homeowners policies will cover accidental damage to your garage door from storms, vehicles, or vandalism.
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However, injuries caused by preventable safety failures—like a non-functioning sensor—may be excluded, especially if the system was knowingly left in disrepair.
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Liability coverage may apply if you’re found not negligent, but insurers may deny claims if you failed to maintain a legally required safety device.
To protect yourself:
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Keep your sensors aligned and functional.
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Never bypass or disable them.
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If the system isn’t working, call a professional technician to restore it to UL 325-compliant operation.
Proper maintenance protects more than just your garage—it helps protect your legal and financial future.
Disclaimer: The information provided in this blog post is for general informational purposes only and is not intended as legal or insurance advice. Laws, regulations, and policy coverage can vary. Always consult a qualified attorney or your insurance provider for guidance specific to your situation. Overhead Door Company of Huntsville/North Alabama™ assumes no liability for decisions made based on the content of this article.
Local Help in Huntsville and North Alabama
If you’re in Huntsville, Madison, Decatur, Athens, Hazel Green, Harvest, Brownsboro, Hampton Cove, Priceville, Tanner, Meridianville, Gurley, Toney, or any surrounding metro area, we can help.
At Overhead Door Company of Huntsville/North Alabama™, we’ve been serving our community since 1968 with:
- More than 3,500 five-star reviews
- Trusted, in-house technicians—never subcontractors
- Same-day service in most cases
- Free estimates over the phone
Whether your issue is a sensor realignment, wiring repair, or full sensor replacement, our technicians are trained to handle it quickly, safely, and correctly the first time.
Final Thoughts
To recap:
- Only the receiver sensor should be green.
- A blinking or off green light means something is wrong.
- Most sensor issues are fixable with a bit of cleaning, realigning, or rewiring.
- If you’re unsure, don’t risk it—call a qualified garage door professional.
Garage door sensors may seem small, but they’re one of the most important safety features on your system. Keeping them clean, aligned, and functional will help your garage door run smoothly and safely for years to come.
Related Resources
- Why Won’t My Garage Door Close?
- Garage Door is Opening By Itself
- Garage Door Opener Only Works Sometimes
- Garage Door Troubleshooting Guide
Need Help Now?
Call 256-772-3674 to speak directly with a local garage door technician.
We’ll give you a free estimate over the phone—no pressure, no call centers, just honest answers from a company trusted in North Alabama for over 55 years.
We look forward to hearing from you!
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A Final Note on Safety
Garage doors operate under extreme tension. Never attempt to repair springs, cables, or internal opener components on your own. If you’re unsure about any part of the troubleshooting process, please give us a call. We’re here to help you stay safe and get your garage door back on track.
