Before beginning initialization of Iridium and GPS components, verify that basic connectivity is available.
Log into the Local Manager and navigate to the modem resource. By default, the modem has no configuration. Use the terminal command to open a session with the modem. Run ATZ and ATi4. You should receive OK and Iridium in response.
[admin@u5000]# modem Iridium [admin@u5000 (modem)]# t Press ~[ENTER] to exit Connecting ... Console session started. atz OK ati4 IRIDIUM
The output of show serial will show CTS and DSR as FALSE. This is normal for this system.
Navigate to the port that the GPS is connected to. Use the config serial command to set the baud rate of this port to 4800 (default for Garmin GPS).
Then, use the terminal command to open a session with the GPS receiver. You will not be able to enter any commands, but you should see NMEA traffic coming across the port. If there is no data or if the characters are garbled, try adjusting the baud rate or swap in another cable.