hell Dennis you've got my sympathy, is there anyway you can open her up for tonight get that north wind blowing through and air it out in time to head off again tomorrow, but I suppose with the cooked wiring she will have to be redone, mate, next time, have a beer for me. keep trying, when you do get out there it is worthwhile

Grizzly

I feel for you mate, but something does not add in what you have written, and may be worth saying in case I am right.

Normally, all trailer connections are linked into the cars system, ie turn indicators to trailer turn indicators, etc. The prime mover (car) has safety systems to blow a fuse BEFORE melting wires, even if addtional connections are made - trailer.

The only exception to that rule is the axcillary connection. This is a "hot wire" from a battery source, to run "other" equipment, but it should also be fused.

What I would look at is none of these to start, as I have seen this happen. Check the "earth" wire "normally white" IS connected through the plug and earthed, also it is earthed on the trailer. If you are handy with a multimeter, this is easy.

Without getting into too much detail, and I am not sure I could explain it well. When the "earth" or grounding wire is not connected, then you have a situation where the electricty will find its own way home, and can produce what you have described.