Got it working in an hour or so. Wiring diagrams and colour codes on the web were no help. What works . . .
MH Utility Trailer function
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white white ground
brown green/black right signal ?
yellow yellow left signal ?
green dark green running lights
brown/yellow N/C
the trailer is from Home Depot
The cause of the MH signal lights going rogue was, of course, one wire connected to another wire from the MH, because of colour code confusion. I have not yet tried using the trailer on the van where the problem didn't occur.
2004 E350 Adventurer (Canadian) 20 footer - Alberta, Canada
No TV + 100W solar = no generator needed