some of the Aristo wiring seems to follow no plan or reason,
on some of mine the battery selector switch changes the direction of the motor but the wheels are still connected meaning the wheels send power back into the track with tha polarity reversed,I discovered that when my Mallet went in the opposite direction to what I was expecting when I connected the battery,, but another loco also decided to move using the power from the mallet, it was like poltergiest, trying to decide which loco to chase as they both were going in oppositte directions,
also they seem to follow no colour coding, if you unplug one plug at a time and power the track you will find out which is the motor and which is the pickups,