Conditions For Running DTC

WARNING: This page is about a different car, the 2003 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.

Engine speed is more than 40 RPM.
System voltage is 7.5-15 volts.

DTC sets if fuel injector No. 1 feedback voltage is 2.6-4.6 volts (ECM pull-up voltage) indicating an open circuit when fuel injector No. 1 is commanded off.