I have a problem. I just finished first layout, less than 100 feet. When I check track voltage using a multimeter on empty track, I get good results (max. of 24 volts) on every section). Then I put my Bachmann Big Hauler loco on it, and the loco doesn’t budge. Voltage on the track drops to less than 2 volts. What is doing this? I suspect wires are crossed in the loco, but I’ve checked and cannot find anything (all black wires go to black, all red wires go to red and nothing seems to be touching). Is motor bad? How do I find the problem? All suggestions are appreciated.