Two things can cause that.. Well really one but it has two causes.
your unit is confused.
Step one: REBOOT, Remove all power both 120 volt AC and 12 volt DC (Turn off by switch, Lift a battery cable, UNPLUG)
Have a cup of coffee, or a cold one (Wait at least 2-5 minutes).
Re-connect and turn on: Problem solved ,, great,, Still have it....
Well, my Xantrex is a prosine it is a bit more informative, the display said "Prosine Memory Error".. Simple translation,,, it had lost it's mind,, The solution was an RMA since it was still under warranty.
I sometimes tell the tale of 3 companies.. Making cuss-some-more non -service call to Hughesnet (7 hours and all I got was a headache), Xantrex, (Aboutr 20 minutes, had RMA within 2 and the rest of the time was a combo of BS (Friendly kind) and suggestions that may have prevented a repeat of the problem, In short a good call to CUSTOMER SERVICE, alas, I hear they have moved that out of the US though.
And to Workorse Custom Chassis, call taken by a human (not a robot) and even thoguh she was only the call director system (the job the robot normally does) when I told her my problem so she could direct it, she told me the solution and solved it,,, Less than a minute, Problem solved (Now that is CUTSOMER SERVICE!!!!!).
This is from the BS/Chat portion of the Xantrex call.
The wire size mentioned in the manual... Try going bigger if you can
And tape the two (positive and negative) wires together for as much of the run as you can You want them side by side, No air between them, (you can also use a split loom) but you want them bundled "Wiring harness" style. i did both, taped together and up-graded wire. That was 9 years ago (the original failed in less than a year).
Home is where I park it!