Originally Posted by Rutrodeo
So maybe thats why there is a short line thats added to the phone line from the remote jus before the inverter, thats where the reversal takes place?
Airstream typically uses a single, continuous cable from the inverter to the remote's location in the galley wall, at least on all of the units that I have worked on. WFCO typically uses a narrow, 4 conductor only plastic RJ-11 'type' plug, but it is too small to properly fit into any standard RJ-11 port which accepts either 4 or 6 conductor RJ-11 plugs. Magnum inverter/chargers require the 6-slot standard RJ-11 plug, which I install onto the existing 4 conductor cable that's present. Victrons use a Cat-5 cable.
You might have an issue with either a cable end or a union if Airstream used one to lengthen an improper length cable. If you have the standard sized RJ-11 cable, you might try reversing one of the end RJ-11 plugs to see if that will get communication between the inverter and the remote.