Theory Of Operation
WARNING: This page is about a different car, the 2014 Dodge Journey. However, it is still accessible from the selected car via links, so may be relevant.
The Telematics Gateway (TGW) controls and monitors both the (X712) microphone 1 input circuit (+) and the (X792) microphone 1 input circuit (-) for a concern. The TGW communicates over the CAN-AT Bus and the CAN-Interior Bus. The microphone is located in the rearview mirror.