DTC B1B42-04: Front Ultrasonic Sensor (LH) Signal Circuit Malfunction (Parking Assist Unit (Ultrasonic)): Outline

WARNING: This page is about a different car, the 2020 Mazda CX-30. However, it is still accessible from the selected car via links, so may be relevant.

DTC B1B42:04 (PARKING ASSIST UNIT (ULTRASONIC)) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	Front ultrasonic sensor (LH) signal circuit malfunction
Detection condition	The parking assist unit (ultrasonic) detects a front ultrasonic sensor (LH) signal circuit malfunction for 11 s.
Fail-safe	(See DTC TABLE [PARKING ASSIST UNIT (ULTRASONIC) (US)] .)
Possible cause	Front bumper malfunction Front ultrasonic sensor (LH) connector or terminal malfunction Parking assist unit (ultrasonic) connector or terminal malfunction Short to ground in front ultrasonic sensor (LH) signal circuit Short to power supply in front ultrasonic sensor (LH) signal circuit Open circuit in front ultrasonic sensor (LH) signal circuit Front ultrasonic sensor (LH) malfunction Parking assist unit (ultrasonic) malfunction
Courtesy of MAZDA MOTORS CORP.