I started a simple project of adding back up lights to my 2 year old travel trailer. Found the correct wire and ran it - I was not happy with the other wiring in the unsealed box that connects the 7 pin to the trailer. I proceeded to "fix" it - Things went well- pretty easy - just match the colors - Hooked up the break away switch - battery power one side - connected to the confirmed blue brake wires - before energizing the system I was checking continuity and found i had continuity to ground. The switch should be non directional and dont believe it is or should be grounded anywhere. Could I have a bad switch that is grounding to the mounting plate ? Dont want to make sparks so I am trying to figure this out before hand. Of course it worked before - and wasnt broke.
Any help is appreciated.

The break switch for the peddle is grounded when it is not activated... don't ask me why but it is. That is the best I can do .... I put an electric brake system in my van and the instructions said that in some Ford vehicles it is this way... it is the most confusing thing I've ever seen. The guy who initially did it wired the connection to the controller wrong and it fried the controller. when I connected to a trailer with electric brakes... I wired it wright by the diagram to a new one but have yet to try and hook to a trailer. Good luck... I think you will be fine...

I’m on RVforum and the guys there are pretty resourceful and helpful if you don’t get all the info you want here.

You can often read a ground that is feeding through other devices (lights etc.) just waiting for voltage to activate the device. If it reads less than a few ohms it may be a short-to-ground and require some further care in checking. You should be reading the actual resistance of the device.