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Home >> Toyota >> 2021 >> 4Runner TRD Pro >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Collision/Avoidance >> Lane Departure Alert System - Diagnostic Codes & Circuit Tests >> Lane Departure Alert System >> DTC U0123: 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 U0142: Lost Communication with Body Control Module "B"; DTC U0155: Lost Communication with Combination Meter [08/2019 - ] >> Description
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DTC U0123: 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 U0142: Lost Communication with Body Control Module "B"; DTC U0155: Lost Communication with Combination Meter [08/2019 - ]: Description

These DTCs are output when a communication malfunction occurs between the sensors and ECUs.

DTC No. Detection Item DTC Detection Condition Trouble Area
U0123 Lost Communication with Yaw Rate Sensor Module 3 seconds after the ignition switch is turned to ON, the vehicle is being driven at 5 km/h (3 mph) or more and a communication error between the yaw rate sensor and the forward recognition camera is detected for approximately 5 seconds or more.
  • CAN communication system
  • Yaw rate and acceleration sensor (airbag sensor assembly)
  • Forward recognition camera
U0126 Lost Communication With Steering Angle Sensor Module 3 seconds after the ignition switch is turned to ON, a communication error between the spiral cable sub-assembly and the forward recognition camera is detected for approximately 5 seconds or more.
  • CAN communication system
  • Spiral cable sub-assembly
  • Forward recognition camera
U0129 Lost Communication with Brake System Control Module 3 seconds after the ignition switch is turned to ON, a communication error between the skid control ECU (brake actuator assembly) and the forward recognition camera is detected for approximately 5 seconds or more.
  • CAN communication system
  • Skid control ECU (brake actuator assembly)*1
  • Skid control ECU (master cylinder solenoid)*2
  • Forward recognition camera
U0142 Lost Communication with Body Control Module "B" 3 seconds after the ignition switch is turned to ON, a communication error between the main body ECU (multiplex network body ECU) and the forward recognition camera is detected for approximately 5 seconds or more.
  • CAN communication system
  • Main body ECU (Multiplex network body ECU)
  • Forward recognition camera
U0155 Lost Communication with Combination Meter 3 seconds after the ignition switch is turned to ON, a communication error between the combination meter assembly and the forward recognition camera is detected for approximately 50 seconds or more.
  • CAN communication system
  • Combination meter assembly
  • Forward recognition camera
  1. *1: for Vacuum Brake Booster
  2. *2: for Hydraulic Brake Booster