If the connection between the Control-RRC and the Radio-RRC is lost the Radio will be kept on for 60 sec = as long as the RED LED on the AUX/Mic jack is ON, When the RED LED goes off the the Radio-RRC stops sending keep alive to the radio and the radio switch off. You can hear the click from the power relay in the radio.
Just verified it 5 minutes ago
It's the same function for all the radios with detachable front.
73 de mike