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Home >> Mazda >> 2021 >> 3 Select, 4D Hatchback, AWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Collision/Avoidance >> On-Board Diagnostic - Vehicle Control Module (2 Of 2) >> DTC U2139-00: Communication Error With Rear Side Radar Sensor (RH) [Vehicle Control Module] >> Outline
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DTC U2139-00: Communication Error With Rear Side Radar Sensor (RH) [Vehicle Control Module]: Outline

DTC U2139:00 [VEHICLE CONTROL MODULE] DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location Communication error with rear side radar sensor (RH)
Detection condition
  • The vehicle control module (VCM) cannot receive CAN signal from the rear side radar sensor (RH) for 10 s.
Fail-safe (See DTC TABLE [VEHICLE CONTROL MODULE (US)] .)
Possible cause
  • Power is not supplied from vehicle control module (VCM) to rear side radar sensor (RH)
  • Malfunction in CAN communication line between vehicle control module (VCM) and rear side radar sensor (RH)
  • Rear side radar sensor (RH) malfunction
  • Vehicle control module (VCM) malfunction
System wiring diagram Not applicable