What Can I Do if My System Says, "Sensor open"?
If a door or window with a sensor is reporting open, you will not be able to arm your system. If your door or window is closed but the keypad is reporting it open, the door or window may not be securely closed, the sensor is out of alignment, or the sensor may be damaged. This can also mean your sensor or magnet has fallen off the door or frame.
Follow these 5 easy steps to fix this:
1. Go to your keypad to identify the zone reporting an open sensor
2. Verify the sensor and magnet are both on the door or window
3. If necessary, reattach the sensor or magnet with double-sided sticky tape
4. While remounting make sure that the magnet and sensor are lined up and that there is no more than half an inch of space between them