Hopefully I'm reading the schematics properly and Zeitronix's website correctly. Their IAT sensor is a two-wire sensor, our OEM is also. They have a signal wire and ground, so does the OEM. It looks like I tap the YL/DG (yellow, dark green?) wire for signal and BR/YL (brown, yellow) for the ground. The yellow/green wire should hook up to the Zt-2's white/brown wire for User2 input (which can be renamed), and the brown/yellow wire will go to the brown wire for a ground on the box. Other than that, everything else is hooked up and I'm pleased with it.