Check Trailer Connection

[TheLoveClaw]

I am fighting a losing battle with my brakes! It's been driving me nuts. Sometimes I have full brakes and other times I run into off and on again check trailer connection, trailer connected messages on the DIC.

I recently removed all the 3-way crush connectors and went to outdoor heat shrink butt connectors. I also installed a new 7-pin pigtail with an outdoor gasket sealed box.

We just got back from Taylor Park and coming over Cottonwood Pass. I got the check trailer connection error message when we left once or twice and then the brakes were on the entire time from Colorado Springs to Taylor Park. Then again on the way back not a single issue until we got back to the Springs. The message would come on and off dinging every time and driving everyone in the truck crazy.

One thing I noticed was the brakes would come on and work but when I took my foot off the brake I would get the error message again. It's almost like a loose wire bouncing off and on but that doesn't explain how it went basically 6.5 hours with no issue and then all the sudden back to bouncing off and on.

Any help would be GREATLY appreciated. This one is driving me bonkers. I just need to know the next thing to look at. I'm getting close to running my own dedicated brake wires but can't hide them under the front cap.

We have had a million issues with this camper (it's the only camper we have bought new) and at this point is considered pure trash by my wife.

2021 Wolf Pack 315Pack12
2018 GMC Sierra DRW Duramax

[TitanMike]

Originally Posted by TheLoveClaw

I am fighting a losing battle with my brakes! It's been driving me nuts. Sometimes I have full brakes and other times I run into off and on again check trailer connection, trailer connected messages on the DIC.



I recently removed all the 3-way crush connectors and went to outdoor heat shrink butt connectors. I also installed a new 7-pin pigtail with an outdoor gasket sealed box.



We just got back from Taylor Park and coming over Cottonwood Pass. I got the check trailer connection error message when we left once or twice and then the brakes were on the entire time from Colorado Springs to Taylor Park. Then again on the way back not a single issue until we got back to the Springs. The message would come on and off dinging every time and driving everyone in the truck crazy.



One thing I noticed was the brakes would come on and work but when I took my foot off the brake I would get the error message again. It's almost like a loose wire bouncing off and on but that doesn't explain how it went basically 6.5 hours with no issue and then all the sudden back to bouncing off and on.



Any help would be GREATLY appreciated. This one is driving me bonkers. I just need to know the next thing to look at. I'm getting close to running my own dedicated brake wires but can't hide them under the front cap.



We have had a million issues with this camper (it's the only camper we have bought new) and at this point is considered pure trash by my wife.



2021 Wolf Pack 315Pack12

2018 GMC Sierra DRW Duramax

The place I would focus on first, based on your description would be the connector (plug and receptacle) where trailer and truck electrical meets.

When not in actual use both are exposed to the elements and corrosion, or just plain loose connections, will cause what you describe.

Another point to inspect is the junction box where the trailer's umbilical cord joins the trailer wiring. Again a point where loose connection can cause this problem.

Also make sure the brake wires are connected to the trailer ground in th junction box as well as the ground (negative) from the umbilical cord. On a tandem axle trailer the brakes can draw >12 amps when fully applied. This requires good connections throughout the circuit.

[TheLoveClaw]

Thanks TitanMike. I will double check the ground wire and see if anything is going on there.

The connector and junction box are both brand new (at least they were for this last trip). I also tried with both connections in the truck. One in the bed and one from the tailgate. Same problem with both. That's what led me to believe the camper wiring was the problem.

Another thing that makes me think it's the camper is I don't have any of the issues with the utility trailer we have.

[Bama Rambler]

On those GM trucks there's a connector on top of the rear end and they are known for having connection issues. It's probably worth checking and cleaning them. I would pull them apart and spray some contact cleaner in them.

[RGrimm]

When I had intermittent brake errors a number of years ago, it ended up being the wires to the brake magnets inside the brake drum. The wire clip that was to hold the positive magnet wire away from the spinning drum came off allowing the positive wire to touch the spinning brake drum, wearing through the insulation and shorting to ground (brake drum) causing a brake error on my F250. The problem was intermittent as bumps would let the bare wire touch the drum intermittently.

It might be worth inspecting the wires inside the brake drums.
-Russ

[TheLoveClaw]

Thank you Bama Rambler and Russ. This forum is so much more helpful than the manufacturer. I'm still waiting for approval for a new gear box land gear from 4 weeks ago.

I have the camper back in storage so checking the brakes will take some time. I will check and clean the connector on the truck and when I get a moment, start pulling the wheels off to inspect the drums.

Thank you again for everyone's response on helping me figure this out!

[TheLoveClaw]

You are the man Russ!!!!

That's exactly what the issue was. The clips fell off and the wire wrapped around the axle. One wire was cut all the way through and the before that the wires were melted and fused together.

All taken care, thanks for everyone's help!

[ebemis]

You know....

SO MANY of the senior and who I consider great resources of info on these boards ALWAYS promote the best way to grease bearings is to remove drums and do it the manual way as it ALWAYS supports a chance to inspect brakes and all other mechanical parts in your hub.... seems like your discovery is another excellent support for that thinking process too!

[RGrimm]

Originally Posted by TheLoveClaw

You are the man Russ!!!!

That's exactly what the issue was. The clips fell off and the wire wrapped around the axle. One wire was cut all the way through and the before that the wires were melted and fused together.

All taken care, thanks for everyone's help!

Glad you found the problem! Intermittent problems are the worst to solve.

Happy Camping and Safe Travels.
-Russ

[KeithF]

I am having the same issue with my trailer! I have done all of the same things you did, and came to the same conclusions. I have butt spliced all my brake connections, replaced the trailer connection cable, and am moving on to replace all the brake magnetic actuators. I haven't taken the hubs off the axles yet, but my brakes are intermittent and I have been getting the dreaded check trailer wiring message now for quite a long time. I believe my problem is the same as yours.

[tomkatb]

Having similar issues.

In our case the brake actuator from Ram was designed not to work well. Eventually failing.

Seems these are afterthoughts on GM and Ram trucks.

The solution for us is an aftermarket controller. 10-30 minute installation.

In these cases, the emergency brake works. The one controlled by the pedal does not. Easy to test.

[KeithF]

As a continuation of my original post, I ordered four new brake magnets and had them sent to the RV Park where I was staying in Montana, courtesy of etrailer.com. I had a down day and went to work on inspecting/replacing the magnets on the trailer. Big job to do in the trailer park. Also, this trailer was purchased new 5500 miles ago and started giving me "Check Trailer Wiring" messages about 500 miles after it's initial maiden voyage. 5000 miles later I decided to look at the magnets after trying to fix everything else.
Take a look at the pictures. The RF and LR magnet wires were cut inside the hub. Also, the retaining clips in three of the four hubs were never installed. Additionally, the wire lengths inside the hub were too long; they didn't pull enough wire through before snugging up with the plastic retainers. The insulation was wearing off the wires. So I was without brakes on opposite wheels AND the wires were shorting out causing the trailer not to have any brakes much of the time. Hence the warning my truck was giving me.



If all else fails, remove your hubs and check the internal brake magnet wiring for broken wires and damaged insulation on the brake magnets.
-KF

[BRinSCupstate]

I’m curious what the clips look like and where they are supposed to be attached. Anyone have a photo?

[KeithF]

The clips I am referring to are here in the pic. Three our of four of the brake assemblies did not have them attached to the lever arm. The flop around inside the hub and eventually break or short out on the brake hub.

[BRinSCupstate]

Originally Posted by KeithF

The clips I am referring to are here in the pic. Three our of four of the brake assemblies did not have them attached to the lever arm. The flop around inside the hub and eventually break or short out on the brake hub.

I see them now. Thank you for pointing them out. Looks like several to go around the magnet lever. Do you think they just fall off or not clipped to begin with?

[KeithF]

Both. I think most were not clipped on though in the first place. The brake lever arm doesn't move very far and I don't think the vibration is extreme. The clips may have been pulled off when they we're pulled from contact with the brake drum.