Wiring center pin on 7 pin connector

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Stapler101

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i need the center pin on my 2017 ram to be wired to the reverse lights to operate surge brakes on a boat trailer.
I tested the pin with truck in reverse. It is not "hot"
Where is the easiest place to find and splice into a backup wire?
I can't believe the pin was not wired. I did not try it in the towing mode. Does anyone know if the center pins are normally wired?
 

quickster2

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Yes they are normally wired and tested at the factory.
 

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i need the center pin on my 2017 ram to be wired to the reverse lights to operate surge brakes on a boat trailer.
I tested the pin with truck in reverse. It is not "hot"
Where is the easiest place to find and splice into a backup wire?
I can't believe the pin was not wired. I did not try it in the towing mode. Does anyone know if the center pins are normally wired?

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Stapler101

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Thanks for the replies.
I retested today and the center pin is not hot with the truck in reverse.
Can I splice into a reverse wire in the trucks wire bundle(if I can locate one)?
 

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Thanks for the replies.
I retested today and the center pin is not hot with the truck in reverse.
Can I splice into a reverse wire in the trucks wire bundle(if I can locate one)?

Watch this video, he gets the reverse wire from the tail light

 

Rampant

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Thanks for the replies.
I retested today and the center pin is not hot with the truck in reverse.
Can I splice into a reverse wire in the trucks wire bundle(if I can locate one)?

My trailer has backup lights and they work without any mods to the truck or trailer. If you just want a hot lead, look at the schematic I posted above. Pin C (dark blue wire) is a variable hot feed for trailer brakes, controlled by the Trailer Tow Module. Pin E (red wire) is a fused hot battery feed. If you are just looking for power, that's the one you want.
 

kabong57

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Did You have the truck running while in reverse ?
 

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Watch this video, he gets the reverse wire from the tail light


This is exactly what I did, had no issues and works perfectly!
 

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Is there a specific reason why you're after the reverse light lead? Do you only want the surge brakes to work in reverse or something?
 

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Is there a specific reason why you're after the reverse light lead? Do you only want the surge brakes to work in reverse or something?

Probably wants to make sure the lockout relay gets power when in reverse so he can back up...otherwise, the surge brakes will lock up and you will have a hard time backing up.
 
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Stapler101

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Mystery solved!
My truck does not have the factory brake controller so the center pin is not wired.
I will splice in as shown in the video so that , when in reverse, the solenoid on my boat trailer will release the trailer brakes.
Thanks for the replies! This site is a gold mine of info .
 

averageguy

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My truck doesn't have a brake controller and the center pin is hot when in reverse. Did you check to see if it has a separate fuse that is blown or maybe its just missing? I have added factory fog lights etc. to cars and the fuse would be missing because it didn't have that option when new.
 

Rampant

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Probably wants to make sure the lockout relay gets power when in reverse so he can back up...otherwise, the surge brakes will lock up and you will have a hard timer backing up.

Ahh that makes sense. Thanks, i've never messed with surge brakes.

OP: It's up to you, but I wouldn't go clear to the tail light housing to do the splice; the harness is right there behind the bumper. Just as a side note: there are several other things triggered by the reverse switch, depending on your trim level, such as reverse cam and the proximity sensors in the bumper. All of those harnesses are right behind the bumper. If you'd like wiring diagrams for any of the other systems, let me know.
 
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Stapler101

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Maybe my stupidity will save someone else!!
When I put the truck in reverse and got out to check the center pin with a test light I did not known the truck "self parked", took itself out of reverse, and therefore the center pin was not hot.
I finally figured that out, exited the passenger door and guess what?? My center pin was wired all along and will release my trailer brakes.
Thanks again to those who read my post and took time to research and reply.
Mike
 

reek

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glad you figured it out!

I was just going to add that if you do tap off the reverse light wire from the tail light harness, use it only as a trigger and wire in a relay to power the 'load' circuit. just saying because the OEM wiring is awfully thin gauged so not sure how much more draw you can add to the factory circuit. Plus with computers now you might trigger a code of some sort.
 
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