Thanks Dr. J.,
I have?the trailer well?grounded, the brake, tail, and running lights all
work. But the electric brakes do not. That is what made me suspect that they
may be polarity sensitive. Not I will look at the magnets and check the
circuit from the trailer plug to the wheel. I already checked at the truck
plug and have electricity there. Trailer lights can drive a guy to drink
pretty quickly her in Wyoming. But then almost anything drives people to
drink in Wyoming.
Joe
> I can conceive of brakes that were polarity sensitive but I believe most
> are not. If the magnet were different colors or marked with a plus and a
> minus, then polarity would indeed be important and you still have to
> complete the circuit and you need a better ground return than the greasy
> rattling hitch ball.