Sorry, I don't have experience with the system but here's a link to LCI owner/service manual for Level Up...
http://www.lci1.com/images/support/manuals/om-levelup-fifth-web.pdf
Specifically, here's the troubleshooting section...
TROUBLESHOOTING
1st - Check the battery in the REMOTE. Replace if necessary.
2nd - Check for POWER into the receiver. If there is no POWER, check the protection device on
the positive wire feeding the receiver. Reset or replace the protection device.
3rd - Check onboard fuses.
4th - When POWER into the receiver is established, check for POWER out to the MANUAL
SWITCHES. The positive wire also has a protection device inline. If there is no power out
to the MANUAL SWITCHES, reset or replace the protection device.
5th - Reprogram remote to the receiver. See “TO PROGRAM THE TRANSMITTER.”
6th - If system is still inoperative, replace receiver. The receiver is common to all units.
I'm guessing that their reference to a protection device is done when installed at GD...probably an in-line fuse or resettable circuit breaker. They also mention onboard fuses which I'm taken to be 12V fuse(s) in the DC fuse panel.
Dave