We have a Grundfos for a domestic water booster application. Everything is set up for constant pressure, discharge pressure sensing and all appears okay, except we cant get the motor to run in "auto". We can run in manual at a constant speed, okay. But we try and go to control, the pump will stop. DI1 is set up as "stop". Now I've tried ground on DI1 as suggested, no change. 5V on DI1, still no change. We have discharge pressure reading, setpoint higher than pressure. Am I missing something simple?