Trailer 7 way plug problem

[Eggscape]

Originally Posted by Tonny LR

I am able to locate the 7 way wire external entry point to the trailer, but inside the trailer, under the bed storage area, I found no wiring junction box. Any idea where is the wiring junction box is located?

Tonny LR

Just follow the wire back to find the junction box on the underside of the trailer frame.
It should look like mine pictured below but without the switch in the bottom.
Just give the nuts a snug but be careful not to short one with another as there is live battery voltage in the box...as there is within the connector.

[Tonny LR]

Hi Eggscape,
Thank you for your 7 way trailer cable junction box location info and picture. It will definitely help me and others if cable and plug needed to be replaced.

Tonny LR

[Mike Lewis]

Originally Posted by tdf-texas

I now use it with the Escape. It works great to keep the 7 pin from getting loose and causing the lights to fail. Adjusted to just slip over the spring-loaded cover on the 7-pin receptacle, it is easy to remove / replace but keeps the cover secured on the 7-pin connector.

That's worth a try. Thanks.

[rubicon327]

Originally Posted by Tonny LR

I am able to locate the 7 way wire external entry point to the trailer, but inside the trailer, under the bed storage area, I found no wiring junction box. Any idea where is the wiring junction box is located?

Originally Posted by cpaharley2008

In the 19 it should be under the driver side front dinette seat,,,

Originally Posted by Eggscape

Just follow the wire back to find the junction box on the underside of the trailer frame.
It should look like mine pictured below but without the switch in the bottom. Just give the nuts a snug but be careful not to short one with another as there is live battery voltage in the box...as there is within the connector.

Ed: The OP has a 2014. Do we know when the change to an outside 7 pin junction box like yours was made? As Jim eluded to the earlier 19's had it under the front DS dinette seat and it looks like I show in the photo. (Ignore the white tubes and the gray Liquid-tite passing through the floor - that is for my mini-split install)

[ichrisdr]

Originally Posted by Tonny LR

Has anyone experienced 7 way plug probems? Thanks.
Tonny LR

YES exact same problem on a brand new 19 that I picked up from Escape last summer. I have a 2015 GMC Sierra. Fortunately it happened on the last day of my 6 week trip back from BC. However I had to listen to the dinging trailer connecting and disconnecting for 10 hours. I didn't read thru this whole thread so this may have been posted. There is a GM service bulletin on this. See attached link.

I was able to duplicate the problem by wiggling the plug and it didn't take much movement to cause it to disconnect. I cleaned the plug and tried dielectric grease, did nothing. I checked the wires all the way back to the junction box, they were fine. I replaced the plug recommended in the service bulletin and so far no problems. It was super easy to just cut the old plug off (I was hesitant to do this) and install the new one.

https://static.oemdtc.com/TSB/SB-10081241-2280.pdf

I used a Pollak Heavy Duty 7-Way plug that was recommended.

[MyronL]

My 7 pin has never come loose because it has a hook held in place at the truck receptacle springed-lid. The wires, though, have pulled out from the plug and no amount of tape will hold.

[sleepy]

Originally Posted by ichrisdr

I was able to duplicate the problem by wiggling the plug and it didn't take much movement to cause it to disconnect. I cleaned the plug and tried dielectric grease, did nothing. I checked the wires all the way back to the junction box, they were fine. I replaced the plug recommended in the service bulletin and so far no problems. It was super easy to just cut the old plug off (I was hesitant to do this) and install the new one.

https://static.oemdtc.com/TSB/SB-10081241-2280.pdf

I used a Pollak Heavy Duty 7-Way plug that was recommended.

Thank you for sharing the GM Bulletin

[Tonny LR]

Originally Posted by ichrisdr

YES exact same problem on a brand new 19 that I picked up from Escape last summer. I have a 2015 GMC Sierra. Fortunately it happened on the last day of my 6 week trip back from BC. However I had to listen to the dinging trailer connecting and disconnecting for 10 hours. I didn't read thru this whole thread so this may have been posted. There is a GM service bulletin on this. See attached link.

I was able to duplicate the problem by wiggling the plug and it didn't take much movement to cause it to disconnect. I cleaned the plug and tried dielectric grease, did nothing. I checked the wires all the way back to the junction box, they were fine. I replaced the plug recommended in the service bulletin and so far no problems. It was super easy to just cut the old plug off (I was hesitant to do this) and install the new one.

https://static.oemdtc.com/TSB/SB-10081241-2280.pdf

I used a Pollak Heavy Duty 7-Way plug that was recommended.

Thank you for sharing the info. The GMC dealer mechanic gave me the same advice without the memo. I bought a POLLAK 12-706 Plastic Blade Style 7-Way Plug from Amazon for $6.54, but is pondering whether to clean the plug first or replace it as you had done it. Would you share what model of Pollak plug that you had used.

Tonny LR

[ichrisdr]

Originally Posted by sleepy

Thank you for sharing the GM Bulletin

No problem.

Originally Posted by Tonny LR

Thank you for sharing the info. The GMC dealer mechanic gave me the same advice without the memo. I bought a POLLAK 12-706 Plastic Blade Style 7-Way Plug from Amazon for $6.54, but is pondering whether to clean the plug first or replace it as you had done it. Would you share what model of Pollak plug that you had used.

It may not hurt to try and clean it. You should be able to duplicate the problem just by backing the truck up and plugging the connector into the truck and wiggling the wire. I found that holding the plug and pushing it to one side caused the issue. It wasn't that the plug was backing out of the truck connector. I hope that makes sense.
I'm pretty sure the one you purchased off Amazon is the one I got. I got mine from etrailer. Pollak Black Plastic, 7-Pole, RV-Style Trailer Connector - Trailer End PK12706.

https://www.etrailer.com/Wiring/Pollak/PK12706.html

Oh one other thing I tried was tightening the connection by bending the metal contacts inside the trailer plug. That didn't help either.

Good luck.

[rubicon327]

This related bulletin has the recommended Pollak model numbers...12-706 included

https://static.nhtsa.gov/odi/tsbs/20...80686-2280.pdf

[ichrisdr]

Originally Posted by rubicon327

This related bulletin has the recommended Pollak model numbers...12-706 included

https://static.nhtsa.gov/odi/tsbs/20...80686-2280.pdf

This one is much easier to understand than the one I attached earlier. Thanks.

[Tonny LR]

Hello ichrisdr and rubicon327,
Thank you for verifing the part # for the trailer plug as suggested by GMC engineers. It was my bad that I did not take time to read it. I am pleased that I got the right one. Thank you all forum members for giving me valueable suggestions and helpfull info. I appreciated everyone of you.

Tonny LR

[luckyone]

Originally Posted by Jack L

I have cleaned my 7 pin connector several times using aerosol contact cleaner to flush out any foreign material and following up with spray lubricant. I would try this before replacing the assembly. Also check the cord for possible damage.

Good advice. I have done the same and that contact cleaner does the trick.

[DenverRTC]

I had the same problem. After trying cloning etc I ended up changing the the connecting cable on the trailer. No problem since then.

[Jim Bennett]

After having to clean the slightly corroded contacts on both sides of the 7-pin connection I used some dielectric grease on it. That has worked wonders for me over the years, rarely having to address the connection at all, other than maybe a wipe and reapply every year or two.

[Tonny LR]

I decided to cut off the Bargman plug and replaced it with Pollack 12-706 plug which fits better and was recommended by GMC to use a Pollak plug to alleviate the poor connection problem. I used ring connectors for the wiring and silicone sealant for water proofing. All signal/indicator lights worked well.

Tonny LR

[fudge_brownie]

I have sanded the contacts on both sides, much harder on the socket side. Also used the CRC Contact Cleaner. Still had problems with one side turn signal and brake light. Finally, a small flat blade screw driver allowed me to squeeze the contacts together inside the trailer side plug. It is working fine for now, it now needs more attentive checking.

[LeonW]

My seven-pin plug came out and I dragged it on the ground for a few miles before I noticed. As a result, it has a nice bevel on one side.

I am thinking of replacing it with this plug that LEDs that light up to make sure the connection is good. i was wondering if anyone has any experience with this plug or other alternatives.

This happened twice on our last trip. It turns out the spring holding the plug top against the plug has weakened. So Looks like I will be searching for a replacement on the vehicle side as well. And I am going to start using the camco multi clamp.

[cpaharley2008]

Leon,
I have been using a thick rubber band or a elastic hairband found on the pavement. Works like a charm keeping that lid tight on the connection.

[Bobbie54]

I had a 4-way plug like that on my last trailer. It was very helpful to have (though the problem was ALWAYS after the plug on that trailer, I could see that immediately.). Now I have a thing that plugs into the 7 way outlet and lets you check via LED lights. But that would be better as it lets you know if the plug itself is making a good connection, not just that the car-side wires are good.