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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 U2124-00: Communication Error With Front Side Radar Sensor (RH) [Vehicle Control Module] >> Outline
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DTC U2124-00: Communication Error With Front Side Radar Sensor (RH) [Vehicle Control Module]: Outline

DTC U2124:00 [VEHICLE CONTROL MODULE] DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location Communication error with front side radar sensor (RH)
Detection condition
  • The vehicle control module (VCM) detects that the front side radar sensor (LH) cannot receive the CAN signal from the front side radar sensor (RH) for 15 s.
Fail-safe (See DTC TABLE [VEHICLE CONTROL MODULE (US)] .)
Possible cause
  • Front side radar sensor (RH) connector or terminal malfunction
  • Short to ground or open circuit in front side radar sensor (RH) power supply circuit
  • Front side radar sensor (RH) ground circuit malfunction
  • Front side radar sensor (LH) connector or terminal malfunction
  • Short to ground in local CAN circuit
  • Short to power supply in local CAN circuit
  • Open circuit in local CAN circuit
  • Front side radar sensor (RH) malfunction
  • Front side radar sensor (LH) malfunction
  • Vehicle control module (VCM) malfunction (built into body control module (BCM))
G13718642Courtesy of MAZDA MOTORS CORP.