Here is a DIAGRAM of how it SHOULD be...
That diagram conflicts with the ones posted in the FiberglassRV Document Center
(Wiring Diagram - 7-Pin Trailer End
, Wiring Diagram - 7-Pin Tug End
) and the version posted at MarksRV
and linked in the FiberglassRV Helpful-Links
section), and with the connector and cable I bought for my Boler, and with the Boler wiring diagram in my manual. The pin assignments agree, but several of the colours are different. I think this comes from applying the colours normally used in 4-pin connections to the 7-pin connector, which usually uses a different scheme.
Page 13 of my 1979 Boler Manual
(see the Document Center - Trailer Brand Manufacturer - Boler
) provides a circuit diagram (from Bargman), and my Boler B1700 has the colour coding as indicated in that diagram.
If the diagram you are using is the Scamp diagram at BolerRV
, it agrees with my Boler and its manual, except that the yellow wire is not connected at the tail lights
. If your Boler follows the 4-pin colour standard, then Gina's diagram would more likely be applicable. Since Boler 1300s typically did not have brakes, perhaps it was wired with a 4-pin connector and corresponding colour codes... but then why would it have the fifth and sixth wires?
In the end, the electricity can't see the wire insulation colour, so I would concentrate on getting the right function on the standard pin (no conflict there). To check the function of the wires in the Boler, once you find the ground then you can touch a live (+12V) wire the end of each of the trailer's wires, and see which lights
go on. That's what I did on my Boler.