"Trailer disconnected" error message - F150

[travellvr]

A newbie here. Took my 2016 16' Bambi on its (and my) first trip with my F150 (also 2016). Several times on the way down to where we decided to stay, I got the"Trailer disconnected" message. Each time, stopped, checked it out, saw nothing wrong. On the way back, same thing, so this time I stopped, took of the sway bar and seemed to be fine, so I thought it was the sway bar.

Took it back to the dealer on another matter and asked them about this problem and to check it out. When I picked it up, they said they could find nothing wrong on their side but we agreed that perhaps the sway bar was too much & I decided to keep it off. Sure enough, on the way home, there goes the old "Trailer disconnected" -- twice. Each time, can't see any issue.

Edit: I should add that this is the first time I've ever towed anything. So all advice appreciated, no matter how basic it seems!

Anyone else have this problem? Any suggestions? I checked the Ford owner's manual and it indicates that this message is related to the brake controller identifying a disconnection. Could use a bit of help here!

[overlander63]

We've had several late model F150s that had electrical/electronic problems dealing with the trailer connection or brake controller. In most cases, a trip back to Fordland was needed.

[xrvr]

Yup, go to the ford dealer.

[OTRA15]

Welcome to the forum!

An intermittent electrical problem like this (assuming here) is tricky for the dealer sometimes. Try to recreate the conditions under which you got the error message, and ask the dealer to try different things too.

Not sure what the right terminology is, but I would ask the dealer to put the vehicle on its computer, and do a full diagnostics, including possibly a hard manual re-boot of the entire system.

If the dealer cannot find the problem, and if it persists, I would start documenting everything via email, and get Ford's customer service 800 number in action. I have read good things about this avenue on other forums.

Good luck!

Peter

[xrvr]

Is the umbilical cord in tightly?

[NorCal Matt]

Welcome to the forums! I towed our 2015 Bambi with our 2014 F150 before upgrading our trailer this fall.

My guess is that it has nothing to do with your sway bars. From what I've seen on this and other forums is that it usually is the electrical connection. Try dabbing some dielectric grease on male connection. Sometimes, even when new, those connections need a little help. Please keep us informed as I'm sure this thread will be helpful once you figure it out.

Matt

[HowieE]

I believe the OEM built in brake controllers send a separate signal to the trailer to confirm connection. Not sure what the return path for that signal is but if it is trailer chassis to TV chassis through the hitch that ground path could be interrupted by road bounce. In that case nothing would ever show during a visual inspection and I doubt very much you will ever find a Ford dealer that would even know about it let along be able to test or fix it.

The first test I would do is make a separate positive ground wire from the trailer chassis to the TV chassis and take a trip or 2. That wire can have a disconnect connection in it so you can remove the trailer when not in use. If this solves the problem you have a poor ground issue most likely corrosion on one of the connections. This could be at the chassis connection or in either of the 7 pin connections.

The signal used for this disconnection alarm is a very weak voltage that is low enough as to not activate the brakes but allow monitoring. That type of circuit is very susceptible poor electrical connections

[The Ice Man]

Next time it happens, unplug and re-plug the umbilical. I think avionstream and NorCal are on the right track, particularly if it happens when you are making turns, changing lanes or some other maneuver that would cause the truck/trailer connection to flex.

[sgschwend]

There are lots folks trying to get past this issue. I had it a month ago on my 2008.

There are grounding points on the truck that folks believe cause the trailer connection sensor to say it is not connected. One is by the battery under the hood the other is in the back near the trailer hitch but on the frame. Both of my ground connections were by screws into the frame, right over the frame paint, no bare metal connections. Ford must be relying on the screw thread to make the connection.

I polished my frame connection points and the eyelet then put everything back together. I did obtain higher 12VDC to the trailer, which is good for the brakes and running lights. But I could never make the error message go away.

One Ford Dealer was quoted in saying to a customer wanting this problem fixed, "you would be better off adding an aftermarket brake controller". That is what I did.

[mefly2]

Originally Posted by avionstream

Is the umbilical cord in tightly?

That was -and still is- our issue if the contacts are not periodically cleaned and "retensioned"

[HowieE]

Here is a comment from one of the Ford Fourms that give a good explanation of the problem

The jumper cable between truck and trailer is a good first step. If that doesn't correct the problem it doesn't rule out a bad ground with the trailer, but it does rule out the connection through the plug. Step two is to follow the cord down the trailer tongue to the junction box and open it up. You will find likely find the ground wire screwed or bolted to the trailer frame at this point. I think you'll find the brake circuits return to this point also and this would be my next suspect. If all this checks out, the problem would have to be in the magnet circuit itself. "Trailer Disconnected" indicates an open circuit and "Trailer Wiring Fault" indicates a short. The brake light circuit has no bearing on this and will not trigger a message.

Also noted was the fact that there had been over 200,000 complaints to ford on this issue. Another comment I read was the issue has existed since the introduction of the OEM controllers in 2009

[Candominium]

I had the same issue with my 2013 F150 and then I started getting a message that the trailer WAS connected when I was NOT towing. The dealership found that a relay and fuse in the fuse panel had not been installed. They said for my year F150, it was not standard even though I had the tow package. Apparently, they assume the majority tow without trailer brakes. This fixed both the intermittent "Trailer Not Connected" as well as the "Trailer Connected" issues.

[billdunlap]

This same thing happened to me with my 2015 F150 and Flying Cloud single axle. I suspect the OEM brake controller used by Ford is at fault. I took my truck to the Ford dealer and they could not find anything wrong. I spent well over $200 to have the trailer connection and brakes checked - no problems found. A work around is to switch the trailer brake setting from "electric to hydraulic over electric." You will not receive the "trailer disconnect" message. This is far from an ideal solution but Ford refuses to deal with the problem. Another possible solution is to have a quality brake controller installed and forget using the cheap unit put in by Ford.

Good luck

[Rocinante]

You need this, or something like it: https://www.amazon.com/dp/B00006LVEU

[Bob662]

I would try following the preceding advice, but most likely the trailer brake controller module (in the panel) is failing. It's replacement is the ultimate fix. Its failure ranges from what you've experienced to that plus it sending an electrical signal to the trailer that will lock the trailer brakes. This can leave you stranded in the most inconvenient circumstances. In my case, it was as I started to pull out of the driveway--fortunately not at some campground in Mudbug, Louisiana.

The all-in cost to replace that controller is about $650 for the 2013 F-150. If the other steps you take don't produce a favorable result, you may want to think about preemptively changing that trailer brake controller module. As a previous post reflects, it has been very prone to failure.

[ShinyPete]

travellvr-

All good advice in the posts above. I do have a couple of thoughts as I have recently experienced this as well on our '15 F150 towing our Pete, a '14 Flying Cloud 27fb twin.

First, put your sway bar back! Seriously, if it did it either way, please use it. Second, sometimes I overlook the easiest stuff, and I did when ours was showing me that message. Sometimes when we made a hard right turn, our umbilical cord from Pete to the truck was getting taught, and moving just enough to give me the disco message. When I stopped and checked, just like you, everything looked OK.

Our particular hitch system has a longer distance from the ball coupler of the trailer to the hitch receiver on the truck, so I had to get some more slack for the umbilical to cure the problem. Some folks even make extensions for their umbilical's if needed. I also put dielectric grease in the plug end on Pete just in case.

It's worth a shot to check, and may be happening to yours. Hope this helps.

[RandyNH]

I'm not quite as quick to assume that all of a sudden the controller or cable or connector just went bad, I'm not saying it can't happen, but...
Trailer brake systems are very dependant on a good ground system, between the truck and trailer. The easiest way to start your troubleshooting is to make a simple jumper, couple alligator clips and 10 guage wire, clip to truck frame and clip to trailer frame. See if your problem goes away (mine did).
If so, somewhere (that's a really big somewhere) in the system is a weak ground point, and you can try to narrow it down through different trial and error attempts, but as long as you use the jumper you're good until you find it. The problem with finding it, is that you pretty much have to replace every connection point in the system as your problem is intermittent and a simple metering probably won't show it without the vibrations and movement you get from going down the road.
If the jumper doesn't fix it, then I would be inclined to start looking at the controller.
What do you have for a weight distribution sway control setup, as these can affect it?

[Wingeezer]

If it is any consolation, the integrated trailer brake system in our GMC has not been without similar erratic problems also.

Back to the dealer many times - and $$$ - while they tried to get it sorted out. It "Seems" ok now after they changed a solid state relay that is part of the system, as well as updating the software in the trailer brake system.

Oh, for the good old days of simple circuitry!

Brian.

[silvereagle2]

I had the same thing happen with my 2013 Ford Expedition w integrated brake controller. I had the dealer check the 7 pin signals and all was well. Turns out I had disconnected lines under the trailer and 2 of my 4 wheel brakes were not working because the wires hanging down behind the wheels had snagged. I had them reattached and reinforced and the problem was fixed. Don't know if this is your problem but go underneath your trailer and look for loose or dangling wires...

[morrismaster]

I am fighting this problem on my 2015 Ford F-150. I have a 2015 Bambi FC 20. I get the error message when I am towing... All the time. Camper Clinic 2 says it is Ford. Ford says it is Camper Clinic 2/Airstream. I also have had problems plugging in the airstream umbilical into the ford. So I have that issue too. I changed out the plug on the AS. Still the same problem. I am putting the AS Plug back on the umbilical and I am taking the AS and truck into Ford to get this resolved. I think it is the Ford connection and Brake Controller. I want the Ford to work and if not I am going to change it all out and also get that magnet plug that holds the connection tightly. I am pretty disgusted with this and I am going on almost 2 years of this.