Park Lamp Relay
WARNING: This page is about a different car, the 2004 Dodge Grand Caravan, 2004 Dodge Caravan, and 2004 Chrysler Town & Country. However, it is still accessible from the selected car via links, so may be relevant.
The park lamp switch is a direct input to the BCM. The BCM sends a PCI Bus message to the FCM informing it to turn on the park lamp relay. The park lamp relay is then powered through low side control of the FCM. This circuit is electronically controlled and continuously monitored for malfunctions.