Do Trailer Running Lights and Brake Lights Run on Same Circuit

Question

Question:

I have no running lights on my trailer and have traced it down to find out they are connected to the trailer brakes some how and i need to figure out a way to bypass this so my lights work and i can get home

asked by: John T

0

Expert Reply:

Your brake lights and running lights are designed to be operated by two different circuits. You'll need to find the running light circuit in your trailer's wiring and then you'll need to run that circuit to the running light assemblies you have. I attached a picture of a wiring diagram and a link below on trailer wiring for you to check out as well.

expert reply by: Jameson C

0

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Answer 1

If your trailer has separate turn signals from the brake lights and you want them to remain that way, you will need to use a special converter. On the trailer side, behind the 7-Way, you will attach the Vehicle to Vehicle Taillight Converter,…

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Answer 2

In order to use a third brake light for both brake and running light signals, you would need to use a light with turn, brake, and running light capabilities such as the Thinline LED Trailer Tail Light part #STL59RB. As most trailers are a 3 wire…

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Answer 3

I suspect your problem is caused by a damaged or corroded trailer connector. Take a look at your trailer connectors, both the socket on your truck as well as the plug on the trailer. Look for green or white corrosion on the pins or sockets of the…

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Answer 4

It sounds as though there is a short or something is mis-wired. Using a circuit tester, like the #PTW2993, check the connection points in the vehicle side connector, to see if there is constant power on the running light circuit (brown wire on the…

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Answer 5

It could be a tow package fuse on the vehicle. Use the owners manual to find the locations of fuses/relays related to the tow package wiring to check them and replace as needed. If the issue is not a fuse or relay then you can test the vehicle side…

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Answer 6

On a trailer the brake lights and turn signals operate on the same wire/bulb. So, it is odd when the turn signals work, but the brake lights don't. There are 3 possible causes for this that are more likely than any of the other possible causes.…

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Answer 7

If I understand you correct you have a trailer with separate turn signals and brake lights that aren't functioning properly because you 2013 Ford F-150's trailer wiring combines those signals on one circuit. If I'm wrong let me know. If…

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Answer 8

Yes, the lighting functions of a trailer 7-way will be fully functional regardless of if a brake controller is installed/functional. The circuits are totally separate. There are many people who use 7-way trailer wiring setups without a brake…

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Answer 9

If you connect the trailer brake light circuit to the trailer brake circuit your brakes would lock up immediately since 12 volts is max braking voltage for trailer brakes. You'd need a brake controller that can vary voltage so that you can apply…

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Answer 10

What the vehicle to vehicle (or vehicle to trailer in this case) does is to take the combined turn and brake signals on a vehicle trailer connector and separates them out so the turn signals and brake lights are separate. When using this converter on…

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Answer 11

The problem you are having is a classic ground issue. If the ground wire to the trailer frame or the tail light grounds are not connected securely to clean, rust and paint free surfaces then when the headlights are turned the extra amperage draw for…

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Answer 12

On my 2004 Dodge Ram (which would be the same as your 2003) the factory trailer connector plug split off from a larger wiring harness on the inboard side of the drivers side frame rail near the rear bumper. There should be a rectangular connector…

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