Climate Control System Network Communication: Notes

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

• FCIM
• IPC if equipped with steering wheel controls
• FDIM (attached to the APIM)

When the FDIM touchscreen or voice commands are used, the APIM sends a function request message over the I-CAN to the FCIM.

When the IPC steering wheel controls are used, the IPC sends a function request message over the I-CAN to the FCIM.

The FCIM receives the climate control selections from pressing the buttons on its own controls (interface), the APIM or IPC and sends the requests to the HVAC module in the following message path:

• The FCIM sends the requests over the I-CAN to the IPC.
• The IPC relays the requests to the BCM over the HS-CAN.
• The BCM sends the requests to the HVAC module over the MS-CAN.

For EMTC systems, the messaging path is followed in reverse for any status updates that need to be sent from the HVAC module to the FCIM, then if applicable, to the IPC or FCDIM (through the APIM).

For DATC systems, the messaging path is followed in reverse for any status updates that need to be sent from the HVAC module to the FCIM, FCDIM (non-touchscreen), FDIM (through the APIM) and IPC message center.