Give it a shot, and let us know. Wonder if there has always been an underlying problem with the horse trailer...

 

I’ve had the trailer 11 years. Always maintained. Pulled it with 3 different trucks.

Its a mystery!

I will be able to drive it soon so will trouble shoot until then.

thanks everyone I’ll give update later

 

I have an oscilloscope and can try to check the signal on my Ram with the built-in brake controller. Considering how the display shows variable braking input to the trailer I'm guessing it uses pulse width modulation. I'm not sure how easy that will be the scope though because the trailer brake controller knows when a trailer is connected and I'm not too thrilled about having to dig into wiring on one of my trailers, especially with the cold snap going through right now. Maybe my service manual will explain how it works....

-Rod