How can I tell if someone has switched the Just Checking system off? 1 - Just CheckingIf you see a grey hashed area on the charts, this means no data has been received during that time frame. If it is only for a brief period and movements can be seen before and afterwards, this is likely due to a temporary loss of signal. However, if it is continuous or if it is preceded by a red line, this most likely means the system has been powered off. In this case, we would suggest visiting the property to perform checks, switch on or reboot the hub, and call customer support to make sure everything is working properly.