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Home >> Mazda >> 2021 >> 3 Select, 4D Hatchback, AWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Drivers Assistance Systems - ADAS >> On-Board Diagnostic - Vehicle Control Module (2 Of 2) >> DTC U2120-00: Communication Error With Forward Sensing Camera (FSC) [Vehicle Control Module] >> Outline
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DTC U2120-00: Communication Error With Forward Sensing Camera (FSC) [Vehicle Control Module]: Outline

DTC U2120:00 [VEHICLE CONTROL MODULE] DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location Communication error with forward sensing camera (FSC)
Detection condition
  • The vehicle control module (VCM) cannot receive CAN signal from the forward sensing camera (FSC) for 10 s.
Fail-safe (See DTC TABLE [VEHICLE CONTROL MODULE (US)] .)
Possible cause
  • Power is not supplied from vehicle control module (VCM) to forward sensing camera (FSC)
  • Malfunction in CAN communication line between vehicle control module (VCM) and forward sensing camera (FSC)
  • Forward sensing camera (FSC) malfunction
  • Vehicle control module (VCM) malfunction (built into body control module (BCM))
System wiring diagram Not applicable