In need of schematic/wiring diagram for 4 wire PS2 tether

put a 9 volt battery to the yellow+ and white- wires. If the motor turns forward correctly then the other two red and black are the power from the rails to the board.

Thanks Joe.

That is not PS-2 that would be PS-1.  Normally, White and Yellow motor.  Red and Black AC power.  But other wires colors have been used.  G

Thanks G. I'm not all that PS savvy. I only have two locos with it and one already got and one is about to get  the Williams treatment due to failures.