Gateway Function
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.
The BCM acts as a gateway module by receiving information in one format and transmitting it to other modules using another format. For example, the BCM receives the vehicle speed data from the PCM over the High Speed Controller Area Network (HS-CAN), converts the data into a Medium Speed Controller Area Network (MS-CAN) message and sends (gateways) the message to other network modules such as the HVAC module and the Audio Front Control Module (ACM). This enables network communication between modules that do not communicate using the same network (HS-CAN or MS-CAN ).