Circuit Description
WARNING: This page is about a different car, the 2003 Pontiac Sunfire, 2003 Pontiac Grand Am, 2003 Oldsmobile Alero, and 2003 Chevrolet Cavalier. However, it is still accessible from the selected car via links, so may be relevant.
Battery positive voltage is supplied directly to the Malfunction Indicator Light (MIL). The Powertrain Control Module (PCM) turns the MIL ON by grounding the MIL control circuit. There should be a steady MIL with the ignition switch in RUN position and the engine OFF.