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Home >> Mazda >> 2023 >> 3 Select, 4D Hatchback >> Repair and Diagnosis (Single Page) >> Brakes >> Traction Control >> On-Board Diagnostic - Dynamic Stability Control (2 Of 2) >> DTC U2121-00: Communication Error With Vehicle Control Module (VCM) [DSC HU/Control Module] >> Outline
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DTC U2121-00: Communication Error With Vehicle Control Module (VCM) [DSC HU/Control Module]: Outline

DTC U2121:00 (DSC HU/Control Module) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location Communication error with vehicle control module (VCM)
Detection condition
  • The DSC HU/Control Module cannot receive CAN signal from the vehicle control module (VCM).
Fail-safe Refer to "DTC Table" and "Fail-safe Function Malfunction Contents Table". (See DTC TABLE [DSC HU/Control Module (US)] .)
Possible cause
  • Malfunction in CAN communication line between vehicle control module (VCM) and DSC HU/Control Module
System wiring diagram Not applicable
Connector diagram Not applicable