Where is the CAN Bus location? Is a wiring diagram available for the PCM&CAN B?

What is your question?

If I'm correct both the (PCM/ECM) and CAN Bus operate together. I'm trying to find the culprit of this malfunction.The OBD2 scan detected a fault code U0100 stating there's no communication.

What makes this problem better or worse?

N/A

How long has your 2007 Mercury Milan had this problem?

about (8) eight weeks