Troubleshooting Trailer Brakes Locking Up When Lights are On and no 12 Volt Circuit Voltage
Question:
I have a 2004 F150 Lariat 4 door and the 12V light on the 7 way tester does not light. I also have issue when I turn on my lights the brakes on horse trailer lock up. Without lights they seem to work fine. Thanks,
asked by: Gene
Expert Reply:
It sounds like somehow the running light circuit got wired to the brake output circuit of the 7-way at the rear of your vehicle, and that is why when the lights are on the brakes lock up.
I would check the wiring of the brake output circuit of your 7-way, I would be willing to bet there are two wires run to it and one of them is the running light circuit that should be run to the correct terminal of your 7-way. Check out the FAQ article I attached on trailer wiring.
Product Page this Question was Asked From
Curt 7-Way to RV Socket LED Circuit Tester - Vehicle End
- Electrical Tools
- Testers
- Circuit Tester
- Tow Function Tester
- CURT
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