[Battery +12V] | [Ignition Switch] | [Starter Relay in Car] | +----> WHITE Wire (Intoxalock In) | [Internal Relay] | +----> GREEN Wire (Intoxalock Out) | +----> Starter Solenoid | [Engine Starts]
Professional installers follow this exact workflow. If you are watching a technician, here is what they are doing: Ignition Interlock Device Intoxalock Wiring Diagram