A new SmartThings defector here…
I migrated a few dozen of the Iris 3320-L Door Sensors to HA (Zigbee2MQTT/SONOFF Zigbee 3). Couple of them went offline for unknown reason but they still appear as online on HA and show the last status (Closed/Temp value). The only way I can tell somethings is wrong is by the flatline in the temperature chart.
I took the battery out of another one as experiment and yep, it got frozen in the “Closed” state with the last temperature reading. No indication that there is a problem whatsoever.
This is really troublesome for home alarm - it wouldn’t detect door getting open while I’d believe everything is alright.
How to reliably know when door sensor is offline?