The 4 YELLOW wires with black stripes will tap into the coil pack outputs at pins 42,43, 57, and 72 on the c1381E plug (if you are unsure which one that is, check a couple of pins and confirm the wires match the colors noted below). It doesn’t matter which of the YELLOW wires go … Continue reading Aux Fuel Wiring Diagram for 2018 Focus ST