Although most wiring is unique to wiring of that specific install but ETRAILER.COM has a couple of diagrams on how the trailers 6-WAY and 7-WAY cables are generally wired. Might give you some points on what to expect.
Matching up the colors is a great idea...
Most everything in todays wiring should have both positive and negative wires going to the lamps and not depending on a frame ground to make the connections. This too depends of who wired the trailer too I guess...
The basic color scheme for RV's is usually BLACK is hot +12VDC and WHITE is GND -12VDC. Any other color wire usually is hot +12VDC.
Other utility trailers follow the automotive industry color scheme being RED is hot +12VDC and BLACK is GND -12VDC... They sometimes get mixed together especially with the trailer safety lights wiring. Using a mulitmeter is best way out...
Roy Ken
My Posts are IMHO based on my experiences - Words in CAPS does not mean I am shouting
Roy - Carolyn
RETIRED DOAF/DON/DOD/CONTR RADIO TECH (42yrs)
K9PHT (Since 1957) 146.52M
2010 F150, 5.4,3:73 Gears,SCab
2008 Starcraft 14RT EU2000i GEN
2005 Flagstaff 8528RESS