Repairing Ground Problem on Trailer With Tilting Bed

Question:

Installed new lights and harnessing on my utility trailer. It does tilt, so your recent article is one source I will explore. This little trailer has a metal bed as I had it installed when the wood began to rot in the humid San Antonio weather. I have filed all wire connections to bare metal. The lights do work, but when I turn on the turn signals, both sides flash. Interestingly enough, one I jack up the rear right side of the trailer even one inch, the lights work perfectly fine!! This leads me to believe that I have a ground problem. HELP...CONFUSED AND FRUSTRSTED.

asked by: Oscar S

Expert Reply:

You do indeed have a ground problem, but no worries-we can get you through this!

A trailer with a tilting bed will typically use a bolt on each side as a pivot which allows the tilting portion of the trailer to move. When the trailer is new, the pivoting mechanism fits together tightly and everything works great. Over time, this connection gets a little loose, and doesn't provide a consistent ground connection. Since trailers use the frame as the ground circuit instead of a separate wire, this can cause some, but not all of your lighting functions to work. Or, it can cause intermittent problems that'll really drive you to the point of conniption! When you applied upward pressure to the rear of the trailer using the jack, you tightened the pivot between the tilting bed and the trailer, which temporarily completed the ground circuit which make everything temporarily work fine.

The fix? It's simple. Get a length of 12 gauge wire like # 12-1-1, add a ring terminal # DW05741-1 on either end to create a jumper. Using some self tapping screws, attach one ring terminal to the tilting portion of the trailer, the other to the stationary part. You'll need to use a piece of wire long enough to allow the bed to tilt, but this should fix you right up.

expert reply by: Mike L