Garage door sensors prevent the garage door from closing if there's something in the way. Sensors are a critical safety feature but can prevent an automatic garage door from working properly. If your sensors or garage door motor is blinking or your door doesn't close, it's a sign you could have faulty sensors. Luckily, you can set most automatic garage doors to a manual mode to bypass the sensors. You can also disconnect the sensors altogether, but doing this will prevent most garage doors from working.

Method 1
Method 1 of 3:

Setting the Door to Manual Mode

  1. 1
    Ensure that the door is closed, if possible. Engaging manual mode on your garage door while it’s open may cause it to come crashing closed if the door spring is damaged. Avoid this by setting it to manual mode while the door is closed.
    • If this is impossible because the door is stuck open, move on to the next step.
  2. 2
    Prop the door up with 2x4s if it’s stuck open. Use 2x4s that are as high as the garage door opening. If you don't have 2x4s that will fit the opening, you can improvise by placing a sturdy item like a shelf in its place. Use a hammer to tap the planks in between the door and the floor on each side of the garage door opening. Using something sturdy to prop up the door will prevent it from slamming shut, even if the garage door spring is damaged.[1]
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  3. 3
    Pull down on the door’s manual release cord. The manual release cord is usually red and located next to the garage door motor. Pull down on this cord to disconnect the trolley from the automatic opening system. Pulling the cord will allow you to manually open and close your garage door.
  4. 4
    Remove the 2x4s and manually close the door if it was stuck open. Have someone help you as you manually close the door. Remove the 2x4s by tapping them out with a hammer as someone holds the handle on the door. Once the 2x4s are removed, slowly and carefully lower the garage door to the closed position.[2]
  5. 5
    Pull the cord towards the garage door motor to open the door. Prevent the manual release cord from getting caught on the garage door tracks by pulling it down and towards the motor when you’re opening the door. If you have trouble doing this yourself, ask someone for help.[3]
  6. 6
    Pull the cord towards the door opening when engaging automatic mode. If you want to set the garage door back to automatic mode, you'll need to pull the manual release cord towards the door opening while simultaneously opening the door. Doing this should reconnect the trolley to the automatic opening system and allow you to automatically open and close the door with the button again.
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Method 2
Method 2 of 3:

Disconnecting Garage Door Sensors

  1. 1
    Disconnect the power to the garage door. Flip the circuit that controls the power to the garage door or disconnect the garage door plug from the wall. It’s important that there’s no power running to your garage door motor or you may electrocute yourself when disconnecting the door sensors.[4]
    • Disconnecting the sensors will prevent most automatic doors from working.
    • If your door doesn’t work when using the switch or button, you’ll have to open and close it in manual mode.
  2. 2
    Locate the garage sensors on each side of the garage door. Garage door sensors are small plastic pieces with LED lights. They are located towards the floor on the left and right of the garage door opening.[5]
  3. 3
    Loosen the wing nut and remove the sensors from their brackets. There will be a wing nut on the side of each sensor. Rotate these counterclockwise with your hands to loosen them. Once you remove the nuts, the sensors should come free from their brackets.[6]
  4. 4
    Cut the wires about 1 inch (2.5 cm) from the safety sensor. Use a pair of wire cutters to cut the white and black wire about an inch from the sensor. If done correctly, you'll have disconnected your safety sensors from your garage door.[7]
  5. 5
    Reattach the cut wires to the new sensors. Strip the ends of the wires that you cut to expose the metal wiring inside of the casing. Twist the black wire that you cut previously to the black wire coming out of the new sensor. Do the same thing for the white wire. Then, secure the sensors in their brackets and tighten the wingnuts to hold them in place.[8]
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Method 3
Method 3 of 3:

Troubleshooting Garage Sensor Problems

  1. 1
    Clear your garage doorway of obstructions. Obstructions will set off the sensors and will prevent the door from closing. Move objects away from the garage door opening and away from the sensors. Your door may open and close properly if you do this.[9]
  2. 2
    Clean your sensors with a microfiber towel. Dirt and debris may obstruct the lens in your sensors and prevent them from working properly. Unlike a rough cotton or wool rag, a microfiber cloth won't scratch the delicate surface of the lens.
  3. 3
    Look for damaged or frayed wires. This could prevent your sensors from working properly. If they are burnt or damaged, cut off the power to your garage door and contact a professional so that they can replace the wiring.
  4. 4
    Ensure that the sensors are properly facing each other. Tighten the wing nuts on both of the sensors to make them sit straight in the brackets. Double check that the brackets are attached properly to the garage doors. Doing this will ensure that the sensors are lining up correctly.[10]
    • If the sensor is working properly, it should show a solid green light.
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Community Q&A

  • Question
    Do garage door sensors have different colored lights on them?
    Aasim
    Aasim
    Top Answerer
    Yes, they do. Green means that there is nothing blocking the path. Amber or red means that there is something blocking the path and someone tried to close the door.
  • Question
    What do I do when one sensor is lit green and the other sensor is not lit?
    Community Answer
    Community Answer
    This could occur when the transmitter is working (lit green) but the receiver is not getting a signal (hence not lit). This could be because they are not aligned or there is something blocking the path between them. You can try bringing them closer together to see, or perhaps clean them. It is also possible they are broken or not installed properly.
  • Question
    Can I bypass the sensors needed to close the garage door?
    Community Answer
    Community Answer
    Yes; however, you will need some additional electronics to do so. For the Craftsman 1/2 HP garage door opener I have, I'd need a signal generator that sends a pattern of 6-millisecond-long 6-volt pulses, followed by no signal for 0.5 milliseconds. This needs to match the signal the sensors send so the garage door works normally. This will vary by model, and it requires an oscilloscope to verify. It may be easier to just tape the sensors together so nothing gets in the sensor's path.
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Things You’ll Need

Setting the Door to Manual Mode

  • 2 2x4 planks
  • Hammer

Disconnecting Garage Door Sensors

  • Wire cutters

Troubleshooting Garage Sensor Problems

  • Microfiber cloth

About This Article

wikiHow Staff
Co-authored by:
wikiHow Staff Writer
This article was co-authored by wikiHow Staff. Our trained team of editors and researchers validate articles for accuracy and comprehensiveness. wikiHow's Content Management Team carefully monitors the work from our editorial staff to ensure that each article is backed by trusted research and meets our high quality standards. This article has been viewed 219,010 times.
199 votes - 29%
Co-authors: 4
Updated: March 5, 2023
Views: 219,010
Categories: Garage Doors
Article SummaryX

To disable your garage door sensor, first, make sure your garage door is closed or propped up with 2 by 4s just in case it comes crashing down when it’s put into manual mode. Once your garage door is secure, pull down on the manual release cord, which should be red and located next to the garage door motor. If you needed to prop up your garage door, have someone carefully remove the 2 by 4s as you hold the door, then carefully bring the door into the closed position. With the door in manual mode, pull the manual release cord toward the garage door motor to open the door. You can put your garage door back into automatic mode by pulling the manual release cord towards the door while simultaneously opening the door. For more help, like how to completely disconnect your garage door sensor, read on!

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