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Home >> Mazda >> 2023 >> 3 Select, 4D Hatchback >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Communication Devices >> On-Board Diagnostic - Body Control Module (BCM) (4 Of 4) >> DTC U2121-49: Communication Error With Vehicle Control Module (VCM) [Body Control Module (BCM)] >> Outline
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DTC U2121-49: Communication Error With Vehicle Control Module (VCM) [Body Control Module (BCM)]: Outline

DTC U2121:49 - BODY CONTROL MODULE (BCM) DETECTION CONDITION AND POSSIBLE CAUSE

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