there is a dedicated pin in the connector for ground.

Sam

 

so should I try to trace that ground wire back to look for problems, or should I reground somewhere else?

I've read in other forums about "trailer disconnected" errors that were seemingly impossible to locate. Similar to my problem, the trailer worked fine on other tow vehicles, and it was an intermittent problem (the disconnect). I will read voltages on the brake and ground pin toinght and make sure I am at least getting that.

 

The problem is most often with the trailer. Maybe other trucks did a better job of grounding through the ball, even though the ground on the trailer was compromised.

But if you are convinced it is the truck, the problem is most often right in the connector at the rear. Take a look and see if you can see evidence of corrosion. Or just get a new one to try. They are not too expensive.

Could just be the plug on the trailer too. Sometimes they make good connection on one truck, and not on another.

 

You can test the trailers brakes by pulling the brake-a-way pin out that should apply full voltage and thus full curent to all the brakes if you can still spin the wheel its the trailer brakes at fault not the trucks. If the wheels lock up soild you've got a power ishue in the truck like bad ground or low curent coming out of the box. You can apply the brakes with a battery thur the trailer conection wire too but you'd need a truck end conector with a pig tail on it ot take apart the trailers outside housing
Pin out is listed here.
7-way - 7 pole RV Travel Trailer Connector Wiring Color Code

44

 

All trailers ground through the pin fed by the white lead, but unless someone did something strange, that is the way your trailer and truck are set up. I haven't seen anyone trying to ground through the ball unless they were doing their own wiring.

Having said that, it sounds like this type of troubleshooting is new to you and it might be simpler to have the dealer check it since you are still under warranty. I have seen several trucks on the lot recently that were new and the controllers or seven pins were not working, so it can happen.

If the RV dealer used their box, they checked two things, the truck's voltage and the amp draw as that box emulates the trailer magnets. Voltage is a basic test, but open circuit voltage is of limited value. The amp draw is crucial as that tells you what happens when the controller comes under a load. If you have voltage and the amp draw falls on its face, you have added resistance from a poor connection somewhere in the circuit or in your controller.

As an aside, in my experience it is the truck and not the trailer 99 times out of hundred. Unless the trailer is very old, I almost never see a problem with brake leads or grounded magnets in the trailer

My two cents worth and good luck!

Steve

 

OK, I'll make an appointment with the dealer and let you know.

Thanks.

 

I took my truck in, first they changed the 7 pin plug, no luck. This last time they changed the TBC module in the dash. I wasn't able to test on my own trailer, but I hooked up to my brothers and the brakes worked great. Hopefully I'll get to mine this weekend.

So it would seem anyway that it was the controller itself.

luckily just at the end of my warranty.

Thanks for your help.