Check with trailer dealer and have them check your plug. More then likely, they crossed the wires in the trailer harness somewhere.

 

Thanks will try that first

 

"Wire Fault on Trailer" no problems yesterday, today it was raining hard, major Fault warnings. Haven't used this in years, RV place looked at it and said they tested everything - including the Ford. They said it was the RV box in the Dash that controls the brakes, said get that replaced. Been a few years since used that trailer so interesting to see it had no problems with a sunny dry hot day, then rain and major problem. It even said " DISCONNECTED from TRAILER" also with a annoying alarm. ( 2008 F350)

 

Any one try to water proof the connections, did it stop the alarms?

 

Can’t believe this post had so many who didn’t know how to deal with this issue. Had a “wiring fault on trailer” flash across my dash of my 2008 f350. I removed the two bolts holding the bracket for my trailer wires, disconnected the plugin, cleaned the connections, put it back together snug and tight and fixed! KISS

read post #32 for a “how to”.

 

I only got this with our 24' deckover. It forced me take a close look and found a bunch of dirt in the 7-pin male on trailer. I could swear that plug never touches the ground but obviously it did at some point.