Malfunction indicates that this sensor is unable to send signals to your security panel and may not trigger an alarm or signal for help in an emergency. All sensors are designed to send half-strength check-in signals to the panel about every hour. If the panel does not receive a series of these the system will report the malfunction. Malfunctions can be caused by a variety of things. If there was a previous report of a low battery for the sensor it is likely the batteries need to be replaced.
If there was not a low battery report, or this is an intermittent issue we recommend taking a look at the panel location. If the panel is within 5 feet of any large metal or electronic object the problem may be caused by interference. We recommend moving the panel at least 5 feet away from anything that could cause interference; items such as TVs, refrigerators, routers, printers.
If the malfunction persists we recommend contacting Customer Support to help resolve the issue.