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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 (1 Of 2) >> DTC B1B38-49: Front Ultrasonic Sensor (RH) Signal Circuit Malfunction [Vehicle Control Module] >> Outline
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DTC B1B38-49: Front Ultrasonic Sensor (RH) Signal Circuit Malfunction [Vehicle Control Module]: Outline

DTC B1B38:49 [VEHICLE CONTROL MODULE] DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location Front ultrasonic sensor (RH) signal circuit malfunction
Detection condition
  • The vehicle control module (VCM) detects that the parking assist unit (ultrasonic) determined that there is a malfunction in the front ultrasonic sensor (RH) signal circuit for 11 s.
Fail-safe (See DTC TABLE [VEHICLE CONTROL MODULE (US)] .)
Possible cause
  • Front bumper malfunction
  • Front ultrasonic sensor (RH) connector or terminal malfunction
  • Parking assist unit (ultrasonic) connector or terminal malfunction
  • Short to ground in front ultrasonic sensor (RH) signal circuit
  • Short to power supply in front ultrasonic sensor (RH) signal circuit
  • Open circuit in front ultrasonic sensor (RH) signal circuit
  • Front ultrasonic sensor (RH) malfunction
  • Parking assist unit (ultrasonic) malfunction
G13718630Courtesy of MAZDA MOTORS CORP.