It's important to test and maintain your door/window sensors regularly. A low battery or physical damage to the sensor can cause irregular activity or false alarms.

Troubleshooting False Alarms

Check the following:

1. Confirm the sensor and magnet are securely mounted. If either piece has come loose or fallen off, the system won't function properly.
2. Check the spacing between the sensor and magnet. They should be no more than 1/2 inch apart when the door or window is closed.
3. Check for excessive movement. The door or window shouldn't shift or rattle when closed.
4. Check the sensor's location. It should be indoors, away from large metal appliances, and in a climate-controlled environment.
5. Replace the batteries — use 2x CR-2032 batteries.

If your door or window sensor shows a "Loss of Supervision" alert, it means the sensor isn't communicating with your keypad.
For troubleshooting steps, please see our Loss of Supervision Troubleshooting article 

If you've received a "Low Battery" message for your door or window sensor, replace the battery as soon as possible to keep the device working correctly. Need batteries? See our article on How to Order Replacement Batteries.

How to Replace the Battery

1. Open the sensor. Find the small perimeter side of the contact sensor (the larger piece) — there's a slot in the bottom middle. Insert a flathead screwdriver into the slot and twist toward you to open it.
2. Remove the module. Turn the cover upside down over your hand so the module slides out.
3. Slide out the old batteries. Use a flathead screwdriver to slide the batteries toward the arrows on the silver battery covers.
4. Insert the new batteries. Place them with the (+) side facing away from the module and up toward you.
5. Reassemble. Replace the module and snap the cover back into place.
6. Test the sensor after replacing the batteries to confirm it's working properly.

Battery Lifespan

Batteries typically last up to 5 years, though frequent use can shorten that lifespan. If you find yourself replacing batteries more often than every 6 months, please contact our support team — this may indicate a device issue.

If your Door or Window Sensor isn't responding when the door or window opens and closes, follow these steps to fix it.

Step 1: Check the Magnet Alignment

Make sure the gap between the two sensor pieces is no more than 1/2 inch. If they're too far apart, the sensor won't trigger.

Step 2: Test the Sensor by Hand

1. Remove the sensor from the door frame or window.
2. Hold both pieces in your hands.
3. Bring them together, then pull them apart — this mimics the door or window opening and closing.
4. Check your Keypad. If it shows the sensor as "open," the sensor itself is working fine. The issue is likely how it was mounted.

Step 3: Check for Metal Interference

Metal doors and frames can block the magnetic signal between sensor pieces, stopping it from detecting open/close events.

Fix: Swap the two sensor pieces so the magnet piece sits on a non-metal surface. Then remount both pieces closer together and test again.

Step 4: Replace the Battery

If the problem continues:

• Replace the battery and test the open/close motion again.
• Battery type: Two CR-2032 batteries.
• Important: Wait 30–40 seconds after removing the old battery before inserting the new one.

Most alarm equipment includes a built-in tamper switch to prevent unauthorized interference. If your panel shows a tamper trouble condition, it usually means the sensor's mounting plate and case aren't fully connected. This most often happens after replacing sensor batteries.

How to Fix a Tamper Alert

1. Check the cover. Make sure the sensor cover is snapped on securely.
2. Reattach it. If it's still loose, remove the cover completely and re-attach it firmly.