From my experience working at a trailer rental as a youngin' :
Solder all connections
Most problems are due to a bad ground. Run a separate ground wire or solder all grounds to the chassis. (Yes you can solder copper to steel)
Cage tail light and protect pig tail at tongue from pinching and pulling.
I'm working on building a heavy duty 5x10 utility trailer and I'm getting close to wiring it. I don't want to go cheap here since it seems like every other trailer I own the wiring is crap, lights work intermittently, and every time they have to be inspected I have to fix numerous connections, etc.
So, what is the preferred method for wiring a trailer? A couple things I can think of is to run every thing in conduit and avoid using any scotch lock connectors (solder everything I guess). Any other tips, pics, etc of good quality trailer wiring or how yall wired trailers you built would be great.
Thanks.
All great ideas, however, I see and have no problem with grounding to the frame (4 different trailers 2 of which I wired), it is a fine conductor. Just connect properly with bolts and star lock washers.
The problem I do see with relying on the frame is not running a ground wire from the truck connector to the frame and relying on the ball or pintle, this will give intermittant problems everytime!
Just my .02!