SnowDogg Part # 16161400B - V-Plow VX Control Harness Complete HPU is the plow side wiring which is plugged in at your plow motor. This harness is only used on the VXF series V plows. One end has a large plug which plugs into the vehicle side wiring, while the other end has power/ground, along with wires which plug to your valves and coils on the plow side.