Trailer connected... then disconnected... then connected again

[rcompart]

Is anyone else having issues with their truck in wet weather? Back on the 15th of January, we had light fluffy snow that was turning into slush as soon as it touched the treated pavement and I started seeing the "Trailer Connected" message in the instrument cluster followed by "Trailer Disconnected". This was accompanied by "Trailer Left Turn Lamps Fault Check Lamps", "Trailer Right Turn Lamps Fault Check Lamps" and Blind spot & cross Traffic alert deact. Trailer Attached" messages. This happened for the entire duration of my drive into work. I could influence the occurrence of the "Trailer Disconnected" message by applying the brakes and the turn lamp faults by signalling after I received the "Trailer Connected" message. The blind spot message was not always present after it said "Trailer Connected" message. I put it up on a lift at work and poked around to see if there was anything obvious but found nothing. I also disconnected/reconnected the trailer connector to inspect for water intrusion or corrosion but found nothing. I had similar driving conditions home that evening but did not receive any warnings but read that SpoiledHappyWife experienced something similar on hers so I figured I'd be revisiting this and fast forward to this morning, it was raining a good amount and I started to receive the same messages again on my drive into work. Has anyone else experienced these issues and if you did, what was the resolution?

 

[John Christopher]

Is anyone else having issues with their truck in wet weather? Back on the 15th of January, we had light fluffy snow that was turning into slush as soon as it touched the treated pavement and I started seeing the "Trailer Connected" message in the instrument cluster followed by "Trailer Disconnected". This was accompanied by "Trailer Left Turn Lamps Fault Check Lamps", "Trailer Right Turn Lamps Fault Check Lamps" and Blind spot & cross Traffic alert deact. Trailer Attached" messages. This happened for the entire duration of my drive into work. I could influence the occurrence of the "Trailer Disconnected" message by applying the brakes and the turn lamp faults by signalling after I received the "Trailer Connected" message. The blind spot message was not always present after it said "Trailer Connected" message. I put it up on a lift at work and poked around to see if there was anything obvious but found nothing. I also disconnected/reconnected the trailer connector to inspect for water intrusion or corrosion but found nothing. I had similar driving conditions home that evening but did not receive any warnings but read that SpoiledHappyWife experienced something similar on hers so I figured I'd be revisiting this and fast forward to this morning, it was raining a good amount and I started to receive the same messages again on my drive into work. Has anyone else experienced these issues and if you did, what was the resolution?

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Isn't your truck an 18 Expy. I would call the dealer and bring it back for evaluation immediately. Taking the pictures was a great idea. Keep us posted with updates.

 

[Spoiledhappywife]

Is anyone else having issues with their truck in wet weather? Back on the 15th of January, we had light fluffy snow that was turning into slush as soon as it touched the treated pavement and I started seeing the "Trailer Connected" message in the instrument cluster followed by "Trailer Disconnected". This was accompanied by "Trailer Left Turn Lamps Fault Check Lamps", "Trailer Right Turn Lamps Fault Check Lamps" and Blind spot & cross Traffic alert deact. Trailer Attached" messages. This happened for the entire duration of my drive into work. I could influence the occurrence of the "Trailer Disconnected" message by applying the brakes and the turn lamp faults by signalling after I received the "Trailer Connected" message. The blind spot message was not always present after it said "Trailer Connected" message. I put it up on a lift at work and poked around to see if there was anything obvious but found nothing. I also disconnected/reconnected the trailer connector to inspect for water intrusion or corrosion but found nothing. I had similar driving conditions home that evening but did not receive any warnings but read that SpoiledHappyWife experienced something similar on hers so I figured I'd be revisiting this and fast forward to this morning, it was raining a good amount and I started to receive the same messages again on my drive into work. Has anyone else experienced these issues and if you did, what was the resolution?

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I have it on video. I’ve spoken with Service Director and plan on stopping in later this week. When we spoke on the phone this wasn’t anything he said he’s heard of before. I’ll let you know what the outcome is.

 

[99WhiteC5Coupe]

I know it's not a 2018 - but I ordered and bought a new 2015 Expediton Limited 4x4 (with the HD tow package).

I have never towed with it, connected a trailer, or even opened the two wiring harness connector covers. The vehicle has never been wrecked or damaged.

Since new, intermittently, and after starting the engine - the dash will display a "trailer wiring fault" message.

I returned it to the dealer but was told that since there were no codes and no TSB's - there was no fix. Of course, it was not doing it when the dealer checked it.

When the message recurred, I took a picture of it and showed the service advisor on my next visit. Same answer. no codes.

I gave up on having it repaired at the Ford dealership. Apparently their techs are code readers, and do not know how to troubleshoot a problem.

Good luck.

PS - The vehicle will also display an intermittent "No Key Detected" message immediately after starting the vehicle. Same answer for that message from the Ford dealership.

 

[stamp11127]

99WhiteC5Coupe best bet would be to get the factory service manual and fix it yourself. One of the benefits is they include system theory of operation from which you can deduce what can cause various messages to be displayed or why it thinks a trailer is connected when one isn't.
They most likely are monitoring the circuit voltage and current draw of the circuits.

 

[powerboatr]

if its a new one yes go to the dealer. let them put the dummy load connector in and see what pops up.

but bear in mind most trailer issues and faults for previous years is a faulty GROUND somewhere on the trailer. it will cause all kinds of weird faults ot pop up and go away. all of my four past fords with IBC that does weird things with trailers is grounds on the trailer and its 7 pin connection or 4 pin.

 

[rcompart]

Neither one of us have yet to connect a trailer. I agree with stamp that it probably has to do with the current sensing logic in the trailer brake control module and either a chaffed wire or compromised connector providing a return path for voltage as the disconnected message appears when you depress the brake pedal. I just had it at the dealer and they said there were fault codes stored but that they were unable to read them out due to not having the newest generation vehicle communication interface so I have to bring it back in when they receive their new equipment. If I can somehow get my hands on a 2018 Expy service manual, I’ll start looking into it myself but with it being so new, nothing is available yet.

 

[Garrett]

Pulled out of an auto car wash and the rest of my drive the car kept alerting me a trailer was connected, the disconnect...infinite loop.

Anyone experience this before?

 

[Spoiledhappywife]

OH NO! Sorry to hear that. My Expedition did it once and I completely freaked out. Thought it was water too. My Expedition hasn't done it since.

We used to have a 2015 Ford F150 and that is the nightmare we went through. Not to be dramatic but when you are towing a heavy load through a canyon with hairpin turns and that error message comes on and off, indicating your trailer brakes are engaged and then not...well it wasn't fun. We ended up at the dealer where the first visit was a flash to the computer. 2nd visit was a wiring harness and the receptacle. (National Backorder) and the 3rd was another receptacle I think. Since we have the need to tow, it was easier to get rid of it.

As I said, mine did it before and hasn't done it since. (Thank goodness).

 

[rcompart]

This was something I dealt with since new. I did a lot of digging and found out that the trailer connector is the culprit. Check for patina on the part of the plug going from the 7-pin connector to the 4-pin connector. You should see some sealant covering 4 holes left over from molding the plug but I'm guessing you'll actually see 4 green spots where the lack of sealant caused the connector to become corroded.