My trailer brakes are locking up randomly and I get a message saying "Trailer Wiring Fault". I thought maybe the trailer brakes heated up and maybe the gain was too high, but now anytime I start the truck I get the message (even w/o towing anything).

Has anyone else had this issue?

 

If you can pull the DTCs, you should get more-specific details about the wiring fault. My sled trailer threw a couple of DTCs indicating a short to ground in the brake/turn lamps, but the message on the dash was just "Trailer Wiring Fault".

 

DTC?

 

Diagnostic Trouble Codes. FORScan will read them for sure; I'm not sure if a generic OBDII reader will be able to get the specific trailer wiring fault or not.

 

Got it, thanks

 

so far my smart connector has been spot on, even when I switched to LED lights, it let me know when one went out. Quite surprising.

 

have you got something plugged in to the trailer brake/light outlets, OP? a rear LED light or something?

 

I was getting that message with one of my trailers. I ended up swapping the taillight out because the license plate bracket was broke and it solved the issue. Check all your wiring. I think what was causing the message was corrosion on the wiring since the light still worked.

Also, I see you have a '15. take it to the dealer or someone with access to IDS to update the calibration on the Trailer Brake Controller. That might fix it too. I kept getting a trailer disconnect message until I would touch the brake then it would say trailer connected. Having the latest calibration fixed the issue.

 

Yep. You have a wiring issue somewhere in the trailer. Just going to have to figure out where it is. Could be a ground or something inside the plug. I've had the issue before where a wire came loose inside my plug and the brake controller wire touched the 12v power post and just locked up my brakes. Best of luck finding the problem.