yestersday (light rain) driving home i hear a beep and notice the display screen says something like trailer brake modular fault...... it just stayed up on the screen for a minute so i slid the brake bar on controller and then the screen said trailer disconnected and cleared the screen. 10 min later it beeped with the message again..... i just hit reset and it wentr away, then again a couple of times more.........
this morning damp but no rain no issues on same drive time trip.......

what is this? harness out back wet or the brake box in the dash?

 

I'd opt for the harness somewhere as the problem first.

Message center displaying "Wiring Fault On Trailer":
This may occur due to water intrusion/corrosion in the trailer connector socket or the connector behind the socket. If corrosion is present, replace the socket and harness and lube with silicone dielectric grease. If there are no signs of water, perform normal diagnosis. Broadcast Message 7052, 7108.