DTC U2133-00: Communication Error With Climate Control Unit (BCM): 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 U2131:00 (BCM) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	Communication error with climate control unit
Detection condition	The body control module (BCM) cannot receive CAN signal from the climate control unit.
Fail-safe	Not applicable
Possible cause	Malfunction in CAN communication line between climate control unit and body control module (BCM)
System wiring diagram	Not applicable