I am glad that the problem was found and corrected. For those who are, or who may (in future times) follow this thread, I'd like to share a related anecdote.

A fellow cat sailor bought a used cat and trailer. He hooked up new lights on the trailer and did the wiring on the truck. Everything worked well when 12 volts was applied to the trailer.

When the trailer was hooked up to the truck, things were not working correctly. I troubleshot the system and here is what I found: The ground wire was securely screwed into the bottom of the steel bed of the truck. [color:"orange"]The bed of the truck was sitting on vibration isolators, resembling motor mounts which, did not allow an electrical connection between the bed and the chassis of the vehicle! [/color]

On a side note, this dielectric isolation of the bed of the truck makes me wonder about static electricy implications.

The lesson learned is that the trailer needs to be connected, via ground wire, to the same hunk of metal that the battery is connected to, not to the electrically isolated bed of some trucks.


GARY
(IBEW)