Question about 1993 Ford Ranger SuperCab

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Trailer lights stop working when tow vehicle lights are turned on

I baught an old used boat and trailer. The trailer is a bit rusted but otherwise very sound. I ran new trailer light wires replaced all bulbs and installed a new wire converter on a 93 ford ranger. All the lights on the trailer work fine untill I turn on the trucks lights then they stop working all together. When the trucks lights a turned back off the trailers lights all work again. I have tried to check all the grounds and even run a ground from the truck directly to the trailer and still the same problem. PLEASE!!!!!! Can some one help me figure this out. Not sure if the marker lights work on the trailer because of this problem. Thank you for any help in advance.

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  • Anonymous Apr 20, 2009

    i have the same problem it sucks the only difference is my running lights dont work at all



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Pull all of the bulbs and try it using a tester to each light. I have seen a bulb that would contact both posts and kill the lights. Hope this helps. Mike

Posted on Oct 01, 2009


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