ADT Door Sensor Says Open? Here’s How to Fix

Whenever the ADT door sensor says open, even if the door is closed, the most common reason remains an inappropriate installation.

ADT sensors support a wide variety of interior and exterior gates such as doors, drawers, cabinets, and everything that opens and closes.

In this guide, we’ll be focusing on ADT door sensors and what could prevent them from functioning properly.

To fix the always open issue with the ADT door sensor, begin with installing the sensor properly. The Magnet and Bracket shouldn’t be more than ¾ inch apart and the door has to be closed all the way in. Lastly, you can replace the sensor battery and perform a reset on your entire ADT system.

Now when the solution is upfront, let’s start with reviewing the step-by-step guide to install the sensor correctly and then proceed with some working solutions.

Why Does ADT Door Sensor Says Open When Closed?

As we’ve already suggested, the most common reason why your ADT door sensor does not recognize open and closed state would be because of an inappropriate installation.

This is why we’ll begin this guide with a step-by-step tutorial on how to install the device correctly.

This would be the only way to exclude this possibility and proceed with some proven solutions, recommended by users experiencing the exact same problem.

Here is how to install the ADT door sensor the right way:

1. Prepare the double-sided tape.
2. Determine the orientation of the Magnet and Bracket.
3. Use double-sided tape to attach the sensor to the door.
4. Place the bracket on the stationary frame of the door.
5. Position the magnet on the door itself.
6. Magnet and Bracket shouldn’t be more than ¾ inch apart.

Even if the setup seems familiar, we strongly suggest reinstalling the entire system to prevent a possible mount or obstruction issue.

This time make sure to follow our guide, so you can confirm whether our installation guide will help or not.

Note: Orientation does not matter as long as the Magnet and Bracket are in close proximity.

How To Fix When ADT Door Sensor Says Open?

To fix the incorrect sensor reading, we’ll start by targeting the minor possibilities and slowly building our way to more complex troubleshooting.

It’s strongly recommended not to skip any of the solutions to solve the issue and also, to understand where the problem was coming from.

Here is how to fix when your ADT sensor only says openly:

Solution #1 Close The Door Fully

Since many users reported that the fault on their side was discovered only when they applied pressure on their door, apparently closing it all the way in.

In case there is an obstruction underneath the door, preventing it from fully closing, will make all the difference between an open and closed state.

In that regard, you should begin the troubleshooting guide by pushing the door and applying mild pressure inwards to determine if the sensor will read correctly.

In case it does, the problem would be in your door, and more specifically, the way the door closes.

Inspect underneath the door as well as the sides for any obstructions preventing the full closure.

However, in case the door closes smoothly and there is nothing preventing the full closure, proceed with the next step.

Note: If you’ve recently replaced your door, the Bracket and Magnet might be misaligned.

Solution #2 Re-Insert/Replace Batteries

A common occasion in which ADT sensors would deliver false alarms or provide an incorrect state is when the battery is running out.

You should first attempt to re-insert the battery and in case that doesn’t help, you should replace it with a fresh unit.

It’s important to exclude the battery possibility before we continue any further since all other solutions consider that the battery is working.

Solution #3 Hard-Reset ADT System

Like almost all pieces of technology, your ADT system is running an operating system that can often produce failures, resulting in the inability of the sensors to deliver the correct state.

The hard reset is the oldest method in the book and it’s perfect for situations like that.

It essentially restarts ALL services and hopefully will solve the problem in a matter of minutes.

Here is how to hard-reset the entire ADT system:

1. Disconnect your ADT main power supply.
2. Wait for at least 60 seconds.
3. Power the ADT system back.
4. Wait for a minute or two until the system is back online.
5. Open and close the door to test if the sensor will read correctly.

Note: You will hear a lot of beeping while the ADT system is restarting.

Solution #4 Clean Contact Points

Sometimes, especially if your sensor is outdoors, the contact sides of your magnet and bracket could be dirty, preventing them from interacting with each other.

To solve this problem, you can take a wet napkin and clean both the magnet contact side along with the bracket contact side.

Make sure that there is nothing in front of the sensor, preventing the data transfer. Check for moisture or any other obstructions.

Clean the components until you’re confident that this possibility is excluded. Only then open and close the door to check if the problem has been solved.

Tip: We strongly suggest testing your magnet and bracket on a different door to exclude the misalignment as a possible cause.

Solution #5 Reset ADT System

The reset frequently is being referred to as “reprogramming” and it basically resets all configurations and settings.

This method is often considered successful since there is not much else you can attempt without the help of an ADT technician.

Here is how to factory reset your ADT door system:

1. Begin with disconnecting the power to the panel.
2. Remove the backplate to access the panel battery.
3. Remove the battery.
4. Locate 3 wires (WHITE, BLACK & RED) connected to the motherboard.
5. Remove the wires out, without disconnecting them from the motherboard.
6. Wait for at least 2 minutes.
7. Reverse the process.

Important: If the battery is connected to the keypad, abort the process and have an ADT technician come over and help.

Thus, to fix an ADT door sensor that doesn’t read the correct door state, begin with re-inserting the batteries and pushing the door all the way in. Next, perform a hard reset on your entire ADT system followed by a factory reset if possible.

Read Next: Why Is My ADT Motion Sensor Blinking Red?

Last Thoughts

If the ADT door sensor says open even when it’s closed, you’re most likely not installing the Magnet and the Bracket properly. In most cases, they are not close enough or the door is not fully closed.

Following our solutions, you should be able to exclude most of these possibilities and get to understand the problem better.

We hope that you were able to solve the problem and in case you’re experiencing any further issues, make sure to reach out to ADT customer service to inspect the problem.