Hello. I need help with the HO Auto reversing system. I'm using it with the Christmas Brill Trolley. I've had the set for a few years and it's run with varying results. Now I can't get the thing to work at all. I first I though it was the transformer so I went on EBay and replaced the transformer with no positive results. I've checked the track connections to make sure they were correct; A-A, B-B and A-B sections at the ends.

I even checked, with a digital electric tester, the  current in the wires leading to the track and both rails showed current which is very strange to me. Shouldn't only one rail have power at any one time? I'm really confused.
I don't know what else it could be.Any help would be appreciated.
Happy Holidays everyone.