Inadvert. Power Output
WARNING: This page is about a different car, the 2002 Chevrolet Malibu. However, it is still accessible from the selected car via links, so may be relevant.
This BCM output displays the state of the inadvertent power relay that is internal to the BCM. The BCM uses this output to provide battery voltage to the courtesy lamps. If the BCM senses that a lamp has been illuminated for approximately 20 minutes after exiting the vehicle, the BCM will turn off the inadvertent power relay to protect the battery from run-down.