You do not have a short, if you did it would blow fuses and possible (depending on model) make your tow vehicle lights stop working, What you have is an OPEN in the ckt and if your tail (parking) lights work than the ground is fine. The White wire is the ground wire. the Yellow wire is Left turn and stop light the Brown is the Running lights (parking or tail as often called) and the Green is the Right turn and Stop.
If your colors do not match then you can hold the trailer end in your hand with the exposed 3 pins to the right then the far left pin is ground, next is running and then left turn / stop and then right turn / stop.
if you installed all new lights and the harness that came with them and matched the colors when connecting than the problem is most likely with your tow vehicle.
Did your truck come factory wired or did someone add a connector, if it is an add on sometimes they use crimp on splices that corrode and stop working, the better choice is to solder and heat shrink the connections.
Last edited by waterfowlhunter
on Wed Jul 29, 2009 3:21 pm, edited 1 time in total.
CPL holder since 1991, NRA Lifetime Member, DU Member, NICET certified
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