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BCM Interface with Remote Function Actuation (RFA) System

The RFA system interacts with the UTD system (part of the BCM operation) in the following ways:
- RFA system sends a UNLOCK (passive or active) message on the serial data line to the BCM.
- Upon receiving a UNLOCK message from the RFA system, the BCM turns the courtesy lamps ON (if ambient light is low) and disarms the UTD system.
- Upon receiving an LOCK message on the serial data line from RFA system, the BCM turns the courtesy lamps OFF, and momentarily sounds the horn and/or flashes the lights (depending on selected personalize options) to indicate security system arming.