The documentation says this about the led:
LED is ON for 100ms, OFF for 200ns:
OFF:
Are you trying to connect to the right port ‘USB(COM)’ ?
If the connection is stuck at ‘Load model element: Target Informations’ you should read [url]USB Driver V3.822 Hangs Downloads]
Reset to the factory setting happens via the AT command ‘AT&F’
Maybe this could help https://forum.sierrawireless.com/viewtopic.php?f=116&t=1907&p=11683&hilit=10k#p11665