[JohnHorton]

We also found that the voltage swing in ours was not enough to swing the DIO port, as the white wire went from 0.4v to 0.7v. To fix this, we just boosted it with a power line to the white wire terminal through a 150k resistor. So, assuming the blue and brown wires are already connected to 12v, we ran the negative pin on the DIO to the negative (blue) wire, the PWR pin on the DIO through a 150k resistor and to the white wire, and the white wire returned to the Signal pin. It gave us far more consistent results. It could detect the retroreflective tape eight feet away.