Control System Logic

Climate Control System Network Communication 

The controls for the climate control system are in 1 or more locations depending on vehicle option content:

• Front Controls Interface Module (FCIM)
• Instrument Panel Cluster (IPC) (if equipped with steering wheel controls)
• Front Display Interface Module (FDIM) (part of Accessory Protocol Interface Module (APIM))

When the Front Display Interface Module (FDIM) touchscreen or voice commands are used, the Accessory Protocol Interface Module (APIM) sends a function request message over the Infotainment Controller Area Network (I-CAN) to the Front Controls Interface Module (FCIM).

When the Instrument Panel Cluster (IPC) steering wheel controls are used, the Instrument Panel Cluster (IPC) sends a function request message over the Infotainment Controller Area Network (I-CAN) to the Front Controls Interface Module (FCIM).

The Front Controls Interface Module (FCIM) receives the climate control selections from pressing the buttons on its own controls (interface), the Accessory Protocol Interface Module (APIM) or Instrument Panel Cluster (IPC) and sends the requests to the Heating, Ventilation, and Air Conditioning (HVAC) module in the following message path:

• The Front Controls Interface Module (FCIM) sends the requests over the Infotainment Controller Area Network (ICAN) to the Instrument Panel Cluster (IPC).
• The Instrument Panel Cluster (IPC) then relays the requests to Body Control Module (BCM) over the High Speed Controller Area Network (HS-CAN).
• Lastly, the Body Control Module (BCM) then sends the requests to the Heating, Ventilation, and Air Conditioning (HVAC) module over the Medium Speed Controller Area Network (MS-CAN).

The messaging path is followed in reverse for any status updates that need to be sent from the Heating, Ventilation, and Air Conditioning (HVAC) module to the Front Controls Interface Module (FCIM), then, if applicable, to the Instrument Panel Cluster (IPC) or Front Display Interface Module (FDIM) (through the Accessory Protocol Interface Module (APIM)).

When an airflow mode, fresh air or RECIRC mode, temperature setting or blower speed is selected, the Front Controls Interface Module (FCIM) sends this selection to the Heating, Ventilation, and Air Conditioning (HVAC) module using the message path described above.

When A/C is selected, the Front Controls Interface Module (FCIM) sends the selection to the Heating, Ventilation, and Air Conditioning (HVAC) module using the message path described above. If the ambient temperature is sufficient, the Heating, Ventilation, and Air Conditioning (HVAC) module then sends the request to the Body Control Module (BCM) over the Medium Speed Controller Area Network (MS-CAN). The Body Control Module (BCM) then sends the request to the PCM over the High Speed Controller Area Network (HS-CAN).