I checked mine by putting a coax cable on the exterior cable input connector, and jamming tin foil into the end, so the wire and the outside nut are shorted. Then I went around to the different outputs and cables and checked for continuity with my multi-meter. I had it set to beep when continuity is made. I also noted what color the cables were.
My cable coax came in all grey to the booster. The antenna coax is white. Out of the booster it is still grey until it hits the splitter, where the two outputs are orange. The booster is the key. I chased my connection from outside, to the booster. The output from the booster split off and one went to the main TV and the other outside. Clear as mud. I mentioned the problem to the service writer at the dealership. He wasn't real thrilled about chasing wires under the skin of the trailer. I talked to the mechanic as well. He fixed the problem, but didn't document it. I'm guessing either they had the input and output mixed up, or the booster was bad. But it works now, and I have the system documented.
FYI - If you pull the booster out of the wall or ceiling, with the soldered on coax connector pointing at you and the button pointing at you, the antenna coax (white) is connected on the left side. The input where the park cable connection comes into the booster (grey) is on the right side. Behind it, is the output coax cable (grey) that goes to the splitter (orange).
Yours may differ from mine, but nothing was really hidden. I just had to do some investigating. I have a picture of the booster and cables, I'll figure out how to post it and do so.
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