No I was answering Joe but describing in basic terms. Remember all signals must come from the tender PS-2 board. Mux needs 5V and PCB ground, plus activation signal (HL circuit wire) from the tender mux. Engine needs PV so the mux makes it via motor wires. Tach needs current limit and they use the mux board to do it.
So what goes up and what comes down can vary by engine but is similar design wise. Some mux are on chassis, other in boiler but lights on chassis etc...
Not all 10 wires have to be used it is just a jumper so boiler and tender can be separated. Some signal up do not go through mux like fan return and element heat return. They are PS-2 board controlled. But they have to get from chassis connection up to smoke unit. G
