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Home >> Toyota >> 2019 >> C-HR LE >> Repair and Diagnosis (Single Page) >> Restraints >> Seat Belts >> Pre-Collision - Diagnostic Codes & Circuit Tests >> Pre-Collision System >> DTC U0100: Lost Communication with ECM / PCM "A"; DTC U0125: Lost Communication with Yaw Rate Sensor Module; DTC U0126: Lost Communication with Steering Angle Sensor Module; DTC U0129: Lost Communication with Brake System Control Module; DTC U023A: Lost Communication with Front Camera Module [02/2017 - 08/2020] >> Description
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DTC U0100: Lost Communication with ECM / PCM "A"; DTC U0125: Lost Communication with Yaw Rate Sensor Module; DTC U0126: Lost Communication with Steering Angle Sensor Module; DTC U0129: Lost Communication with Brake System Control Module; DTC U023A: Lost Communication with Front Camera Module [02/2017 - 08/2020]: Description

These DTCs are stored when a communication malfunction occurs between ECUs that perform pre-collision control.

DTC No. Detection Item DTC Detection Condition Trouble Area
U0100 Lost Communication with ECM / PCM "A" When driving the vehicle at a speed of 5 km/h (4 mph) or more, a communication error between the ECM and the millimeter wave radar sensor assembly is detected for approximately 5 seconds.
  • CAN communication system
  • ECM
  • Millimeter wave radar sensor assembly
  • Wire harness or connector
U0125 Lost Communication with Yaw Rate Sensor Module When driving the vehicle at a speed of 5 km/h (4 mph) or more, a communication error between the yaw rate and acceleration sensor (airbag sensor assembly) and the millimeter wave radar sensor assembly is detected for approximately 1 second.
  • CAN communication system
  • Yaw rate and acceleration sensor (Airbag sensor assembly)
  • Millimeter wave radar sensor assembly
  • Wire harness or connector
U0126 Lost Communication with Steering Angle Sensor Module When the ignition switch is ON, a communication error between the steering angle sensor (spiral cable with sensor sub-assembly) and the millimeter wave radar sensor assembly is detected for approximately 4 seconds.
  • CAN communication system
  • Steering angle sensor (Spiral cable with sensor sub-assembly)
  • Millimeter wave radar sensor assembly
  • Wire harness or connector
U0129 Lost Communication with Brake System Control Module When the ignition switch is ON, a communication error between the skid control ECU (brake actuator assembly) and the millimeter wave radar sensor assembly is detected for approximately 3 seconds.
  • CAN communication system
  • Skid control ECU (Brake actuator assembly)
  • Millimeter wave radar sensor assembly
  • Wire harness or connector
U023A Lost Communication with Front Camera Module After the ignition switch is turned ON, a communication malfunction occurs between the millimeter wave radar sensor assembly and forward recognition camera.
  • CAN communication system
  • Forward recognition camera
  • Millimeter wave radar sensor assembly
  • Wire harness or connector