DTC U0073-00: Can System Communication Error (Can Bus No. 1): Outline

WARNING: This page is about a different car, the 2020 Mazda CX-30. However, it is still accessible from the selected car via links, so may be relevant.

DTC U0073:00 (PCM, SKYACTIV-G) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	CAN system communication error (CAN Bus No. 1)
Detection condition	Malfunction in CAN bus communication line.
Fail-safe	Not applicable
Possible cause	CAN bus communication line malfunction PCM malfunction
System wiring diagram	Not applicable
Connector diagram	Not applicable