A/C Selection
WARNING: This page is about a different car, the 2014 Lincoln MKX and 2014 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.
When A/C is selected, the FCIM sends the selection to the HVAC module using the message path described above. If the ambient temperature is sufficient, the HVAC module then sends the request to the BCM over the MS-CAN . The BCM then sends the request to the PCM over the HS-CAN .