Originally Posted by Rock Chuck
We have a small camp trailer that we pull with our Toyota Highlander. I recently pulled it 600 miles with no problems. Then last week the trailer brakes quit working. The controller gave me an OL light which means a short in the system somewhere. I tried the trailer on the pickup and it worked ok. I then plugged a different trailer into the Toyota and got the OL light. That pretty well narrows it down to the wiring in the car.
I went over it repeatedly and couldn't find any shorts between the controller and the light plug. I finally ran new heavier power and ground wires the whole way. Same problem. The plug was new this spring, Hopkins brand. It took a bunch of time with a multimeter but I found that it was shorting inside the plug. It's a factory defect that sent the power from the brakes to the right turn lights. I had another new in the box Hopkins plug so I swapped it for a new one. Same problem. Hair tearing time. What are the odds of getting 2 factory defective plugs at the same time, but that's what I had.
I had yet another Hopkins plug that was in good shape. This one wasn't new but it was a more expensive type with the wires molded in so no screws are involved. It's just attaching the car wires to the plug pigtails. This time it's working again.
I wasted many hours tracking the dang thing down. The problem is that the blades in the plug wear through the rubber between them and the 2d one I tried was broken through from the factory. Hopkins is pretty low on my recommended company list right now.



Move to Montana, no one up here has any trailer lights working at all and no one seems to care…


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