Fix door/window sensor connectivity issues for your Xfinity Home security system

Use this guide to troubleshoot common door/window sensor issues with Xfinity Home Security, Xfinity Smart Home, and Shield Select, including pairing problems, low battery alerts, tamper messages, incorrect sensor status, communication issues, and offline sensors.

Before troubleshooting, confirm the following:

• The sensor battery tab is removed.
• The sensor is within 10 to 15 feet of the hub, touchscreen, or gateway during setup or troubleshooting. 
• The Xfinity app is up to date.

Door/window sensor shows open when closed, or closed when open

What you may see:

• The app or touchscreen shows the sensor as open when the door or window is closed. 
• The app or touchscreen shows the sensor as closed when the door or window is open. 

Steps to resolve:

1. Check that the sensor and magnet are installed within a quarter inch of each other.
2. Make sure the alignment marks or indicators line up when the door or window is closed.
3. Open and close the door or window to confirm the status updates correctly.

If still not working, contact us for assistance.

Door/window sensor will not pair

What you may see:

• The sensor does not connect during setup.
• The app or touchscreen does not detect the sensor.
• Pairing fails or does not complete.

Steps to resolve:

1. Confirm the battery tab has been removed.
2. Move the sensor within 10 to 15 feet of the hub, touchscreen, or Xfinity Gateway.
3. If you have Xfinity Home Security and are pairing a replacement sensor, review how to use an Xfinity Home kit to replace a device.
4. If you have Xfinity Smart Home or Shield Select, review how to pair and install door/window sensors. 
5. Try pairing the sensor again.

If still not pairing, contact us for assistance.

Door/window sensor requires a restart

What you may see:

• The sensor is not responding as expected.
• The app or touchscreen status does not update after opening or closing the door or window.
• Troubleshooting steps ask you to restart the sensor.

Steps to resolve:

1. Restart the door/window sensor: 
   
   • Remove the battery.
   • Wait a few seconds.
   • Reinsert the battery.
2. Check the app or touchscreen to confirm the sensor status updates correctly.

If still not working, contact us for assistance.

Door/window sensor battery is low

What you may see:

• You receive a low battery alert.
• The touchscreen or app shows the sensor battery is low.

Steps to resolve:

1. Replace the battery within two weeks of getting the low battery alert.
2. After replacing the battery, check the app or touchscreen to confirm the alert clears.

If still not working, contact us for assistance.

Touchscreen displays a tamper message

What you may see:

• The touchscreen displays a tamper message for the door/window sensor.
• The sensor may appear open, loose, or not fully closed.

Steps to resolve:

1. Confirm the door/window sensor is fully closed.
2. Check that the sensor cover is securely attached.
3. Remove and replace the sensor battery.
4. Check the touchscreen to confirm the tamper message clears.

If still not working, contact us for assistance.

Touchscreen displays a communication lost message

What you may see:

• The touchscreen displays, "Communication lost with your door/window sensor."
• The sensor may not update its open or closed status.

Steps to resolve:

1. Restart the door/window sensor:
   
   • Remove the battery.
   • Wait a few seconds.
   • Reinsert the battery.
2. If the message remains, replace the battery with a new one.
3. Check whether the touchscreen was moved from its originally installed location. If it was moved, return it to the original location.
4. Check the touchscreen again to confirm the message clears.

If still not working, contact us for assistance.

Xfinity app displays a sensor offline message

What you may see:

• The Xfinity app displays, "Door/window sensor offline."
• The sensor is not being detected in the Xfinity app.
• The sensor status may not update when the door or window opens or closes.

Steps to resolve:

1. Restart the door/window sensor:
   
   • Remove the battery.
   • Wait a few seconds.
   • Reinsert the battery.
2. If the message remains, replace the battery with a new one.
3. Check whether the gateway was recently moved or whether a large object, such as furniture, appliances, or electronic devices, was placed between the sensor and gateway.
4. If needed, return the gateway to its original location or clear large objects between the sensor and gateway.
5. Check the Xfinity app again to confirm the sensor shows online.

If still not working, contact us for assistance.

Additional information

Visit our Online Support Center to find common solutions.

The easiest way to activate, manage, and troubleshoot your Xfinity experience is with the Xfinity app! Get 24/7 real-time support, pay your bill, view plan details, get outage updates, and more. Download the free Xfinity app, or scan the QR code with your smartphone.

Need additional support? Ask Xfinity Assistant.