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A/C Switch Status/Evaporator Temperature Status

When the ignition is in the RUN position, the Body Control Module (BCM) monitors the evaporator temperature and the status of the A/C switch (manual A/C only) or the current status of the ATC system. Based on this information, the BCM sends a CCD message to the powertrain control module (PCM) indicating the A/C switch status and the evaporator temperature status.