# Trailer Wiring help...

**URL:** <https://forums.speedlife.net/t/trailer-wiring-help/55910>\
**Category:** NYSpeed Automotive\
**Created:** [October 3, 2008, 5:14pm UTC](https://forums.speedlife.net/t/trailer-wiring-help/55910 "2008-10-03T17:14:20Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![travisn](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/travisn/32/5046_2.png) [@travisn](https://forums.speedlife.net/u/travisn)\
**Post date:** [October 3, 2008, 5:14pm UTC](https://forums.speedlife.net/t/trailer-wiring-help/55910/1 "2008-10-03T17:14:20Z")

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I am in the process of putting a trailer on my 93 civic hatch. i attempted to wire up the flat 4 harness and i got the turns hooked up ok, but when i hooked the brake wire up it allowed the turns to back feed to each side.

anyone have a diagram i can use? do i need a diode or two? should i tap the brake off of the 3rd brake light wire (since brake and turn is the same wire)?

thanks,

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**Author:** ![BDR5oh](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/bdr5oh/32/7315_2.png) [@BDR5oh](https://forums.speedlife.net/u/BDR5oh)\
**Post date:** [October 3, 2008, 5:18pm UTC](https://forums.speedlife.net/t/trailer-wiring-help/55910/2 "2008-10-03T17:18:08Z")

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yes … you need a diode pack … they sell them at Colton,Camping world, … basically any place like that

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**Author:** ![travisn](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/travisn/32/5046_2.png) [@travisn](https://forums.speedlife.net/u/travisn)\
**Post date:** [October 3, 2008, 5:36pm UTC](https://forums.speedlife.net/t/trailer-wiring-help/55910/3 "2008-10-03T17:36:32Z")

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i think i saw one at autozone for like 20 bucks, should i buy it or make one. diodes are like .35 each

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**Author:** ![BDR5oh](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/bdr5oh/32/7315_2.png) [@BDR5oh](https://forums.speedlife.net/u/BDR5oh)\
**Post date:** [October 3, 2008, 5:43pm UTC](https://forums.speedlife.net/t/trailer-wiring-help/55910/4 "2008-10-03T17:43:22Z")

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buy it …

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**Author:** ![travisn](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/travisn/32/5046_2.png) [@travisn](https://forums.speedlife.net/u/travisn)\
**Post date:** [October 3, 2008, 6:50pm UTC](https://forums.speedlife.net/t/trailer-wiring-help/55910/5 "2008-10-03T18:50:24Z")

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haha ok. thanks

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**Author:** ![JayS](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/jays/32/15375_2.png) [@JayS](https://forums.speedlife.net/u/JayS)\
**Post date:** [October 3, 2008, 7:37pm UTC](https://forums.speedlife.net/t/trailer-wiring-help/55910/6 "2008-10-03T19:37:25Z")

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You problem is the fact that almost every jap car ever made has separate lights for the turn signals and brakes. As you’ve found you can’t just splice them together and hope it works. They make a specific devices that allows you to run the multiple turn/brake outputs to a single set of outputs for the trailer where the turn and brake are they same light. For less than $20 it’s well worth it.

Despite the claim on the box that the device is weather proof I highly recommend mounting it inside the car, like in the access area behind the taillight. I installed one in my old Tercel and it was still working 5 years later when I got rid of it.