Lights On Warning

The instrument panel cluster (IPC) activates the lights on warning as requested by the body control module (BCM). The BCM sends a GMLAN message to the IPC indicating the chime frequency (fast rate) and duration (continuous). The lights on warning sounds when the following occurs:

• The ignition is OFF.
• The BCM determines that the driver door is open (signal circuit is low).
• The BCM determines that the headlamp switch is in the PARK or HEAD position.