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Discussion Starter #1
So to start out, for a while ive had the issue of "service trailer brake" showing up on my DIC whenever there would be alot of rain, trailer not hooked up. Been ongoing for a while and never really thought much of it. Fast forward to today, went to move the camper to the inlaws new house. All my lights work, except my truck doesnt recognize the trailer brake, when i hook up the message "trailer connected" doesnt come up on the DIC. I also have no output showing on my integrated controller. And as evident by the short ride i took it on, the brakes arent working. My question, what could be the potential issue? The camper is a 2015 so highly doubt its the trailer. The wiring harness behind the 7 pin is all jacked up, looks like there was some splicing done by the previous owner. All I need is for the 7 pin in the bumper to work, im not concerned about the one in the bed for a 5er since i dont have one to pull. I was thinking of getting a new wiring harness for back there, is there a brake control module under the truck somewhere? Have a trip coming up in less than a month and need to get this sorted out before hand.

Thanks for any suggestions!
 

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Check all the fuses in relation to the system?
Abs, cruise control, trailer brake, ect.
Bad wiring is a common point of failure since the ITBC is finicky for lack of a better term.
 

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Discussion Starter #3
Ill have to check the fuses out. Next day or 2 ill pull down the wiring harness behind the 7 pin and see what im working with.
 

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The Integrated brake system will not show using a test light, at the 7 pin, like old units.
When connected, it senses the trailer, and then turns on the brake system. Water gets into the connector and that can affect the operation- Of course if the wiring is chopped up, you should repair that first. NAPA does carry some 7 pin wire and trailer connector parts.

Some have made a connector using a headlamp as a load, just to check the brake system- that works, and is easier.
 

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Discussion Starter #5
Thanks! Thats good info. Ill definitely be checking it out asap, looks like tomorrow will be a wash. The odd thing, i used to always get the "service trailer system" warning when it would rain and everything would get soaked. Today it rained and was expecting the same warning to come up but never did.
 

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You should take the bumper connector apart- water in the connector can cause problems as it is not sealed very good. Packing with dielectric grease helps.
 

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Discussion Starter #7
I'll probably just end up getting a new connector, this one is original to the truck and im sure is due for replacing. Maybe ill replace the plug first and see if that helps, go from there.
 

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Buy one of the pre-made plug-n-play harnesses for your truck, either OEM or aftermarket. They work just great and eliminate many of common problems such as you suffer. Also, if your truck is equipped with camper wiring, locate the end of the camper wiring, make sure it is dry and coat the end of the blunt cut wires with dielectric grease, cover it with 2 or 3 layers of good plastic and tape it so that it will not come undone. Others have suggested cleaning the truck's 7-way connector and that is also essential.

Report back when you have done this, please.
 

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Discussion Starter #9
Buy one of the pre-made plug-n-play harnesses for your truck, either OEM or aftermarket. They work just great and eliminate many of common problems such as you suffer. Also, if your truck is equipped with camper wiring, locate the end of the camper wiring, make sure it is dry and coat the end of the blunt cut wires with dielectric grease, cover it with 2 or 3 layers of good plastic and tape it so that it will not come undone. Others have suggested cleaning the truck's 7-way connector and that is also essential.

Report back when you have done this, please.
Thanks! I was looking around, think i found the wiring harness i need, dorman makes it. Ill swap out the 7 pin plug first, and while im at it check the wiring (which im sure ill end up replacing) Ill definitely post back on my findings.
 

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Discussion Starter #10 (Edited)
Well just managed to crawl under the truck for a few. I disconnected the 7 pin. All corroded inside. Already have a new one coming. I then disconnected the 2 way adaptor for the 5th wheel. Whoever installed did some splicing, lots of corrosion. I snipped off the old connector that hooks up to the 5th wheel 7 pin just to cover it up for now. The OEM plug that connects into the bumper mount 7 pin plug is in OK shape, has a little corrosion. My question, can i source a replacement for the OEM trailer 7pin? Its not in bad shape just one pin has a slight amount of green corrosion on it. Would i be better off cleaning it up as best i can and filling it up with dielectric grease?
 

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NAPA auto parts has a good selection of trailer wire and connectors. Might check them.
 

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My question, can i source a replacement for the OEM trailer 7pin? Its not in bad shape just one pin has a slight amount of green corrosion on it. Would i be better off cleaning it up as best i can and filling it up with dielectric grease?
Are you talking about the receptacle with the spring door on it?
15932302
Reese and Draw tite offer 'em too.
 

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Discussion Starter #13
Are you talking about the receptacle with the spring door on it?
15932302
Reese and Draw tite offer 'em too.
Nope, the actual plug on the harness that plugs into the back of the receptacle.

Im gonna try and clean it up, theres only minor corrosion on the one pin. My girlfriend works parts department at a ford dealer. She called one of the local chevy dealers that they deal with, apparently cant get just that plug without buying a whole wiring harness for the truck lol. But apparently if you pull the pin out of the plug GM sells the replacement pins. Ill try cleaning it up first before trying that. Have a new receptacle on its way. Picked up some contact cleaner and a fresh can of dielectric grease today.
 

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Discussion Starter #15
Take a look at part # 15354653 service 15306164. I THINK this is the part you want.
Just looked it up, yep thats it! LOL so much for the stealership knowing. Thanks! If i need to i'll definitely order #15306164. Should be alright though, only minor green on the one pin, as you can see. I'll clean it up really well and seal it up.

Untitled by Nick Wierzbicki, on Flickr
 

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If that is the mounting position shown in the picture, that's the grounding pin that's corroded.
 

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Discussion Starter #17
Sorry it took so long to get back. I ended up using a bit of contact cleaner, a small jewelers file and cleaned up the OEM connector as best as i could. Blew it all out with the compressor, added dielectric grease and hooked it into the new 7 pin receptacle. So far so good! No service trailer brake warnings, trailer brakes work now. Before even in light rain i would get the service trailer brake warning, rained pretty good today and nothing!
 
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