Problem with truck or trailer brake wiring

[theick]

I have a 2015 Silverado 3500 with the factory trailer brake controller. I'm getting the error to "check the trailer wiring" with the trailer hooked up but no error without the trailer. According to the manual that means the problem has to be in the trailer. However, shouldn't I be getting voltage from the truck at the brake (blue) wire when I manually apply the brakes at the switch? I don't get any kind of signal at the truck 7 pin when hitting the brakes or using the manual brake lever. I have replaced both the switch in the dash as well as the controller at the back of the truck.

[powerhaulic]

check the fuse under the hood, i have has it blow and create the same message

[jhplak325]

My understanding from reading on other forums is that you will not get a voltage reading at the bumper plug without any thing hooked up.

 

You need to check the wiring on your trailer and stop throwing parts at the truck, it could be something as simple as just the trailer plug. GM even has a TSB out on using a Pollak trailer plug.

 

Others have found bad grounds, brake magnets and bad wiring on their trailers. This goes for even new trailers.

 

Easiest way to check the truck is to hook up to another trailer.

[crankman]

I would try another trailer if possible, but I get that signal every once and a while with mine 2015 2500. It will come on and go off just that fast. I pull the same trailer with a 2008 1500 never a problem with nothing. I understand from another post in this section that the newer trucks sent a pulse single every so many seconds to test the wiring and if it aint perfect it throws that code. I have a very tight fitting 7 prong round connector but it still does it off and on.

[jvbronco]

mine does the same thing. seems to be very sensitive to dirty wiring forcing a poor connection. I have to clean the plug on the trailer end on a regular basis.