Lights On Chime

The radio activates the lights on warning as requested by the Body Control Module (BCM). The BCM sends a class 2 message to the radio indicating the chime frequency of a fast rate and at a continuous duration.
^ The ignition is OFF.
^ The BCM determines that the driver door is open and the signal circuit is low.
^ The BCM determines that the headlamp switch is in the park or head position.