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Home >> Toyota >> 2021 >> C-HR LE >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Drivers Assistance Systems - ADAS >> Dynamic Radar Cruise Control System - Diagnostic Codes & Circuit Tests >> Dynamic Radar Cruise Control System >> DTC U0100: Lost Communication with ECM / PCM "A"; DTC U0122: Lost Communication with Vehicle Dynamics Control Module; 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 U1104: Lost Communication with Cruise Control Module [02/2017 - 09/2019] >> Procedure
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DTC U0100: Lost Communication with ECM / PCM "A"; DTC U0122: Lost Communication with Vehicle Dynamics Control Module; 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 U1104: Lost Communication with Cruise Control Module [02/2017 - 09/2019]: Procedure

  1. CHECK FOR DTCs (RADAR CRUISE 2) 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [02/2017 - 08/2020]

      Powertrain > Radar Cruise 1 > Clear DTCs 

      Powertrain > Radar Cruise 2 > Clear DTCs 

    2. Make sure that the DTC detection conditions are met.

      HINT: 

      If the detection conditions are not met, the system cannot detect the malfunction.

      1. Turn the ignition switch to ON.
      2. Turn the dynamic radar cruise control system on using the cruise control main switch (ON/OFF button).
      3. Drive the vehicle at 5 km/h (3 mph) or more for 5 seconds or more.
    3. Check for DTCs.

      Refer to DTC CHECK / CLEAR [02/2017 - 08/2020]

      Powertrain > Radar Cruise 1 > Trouble Codes 

      Powertrain > Radar Cruise 2 > Trouble Codes 

      Result

      Result Proceed to
      DTC U0100, U0122, U0125, U0126, U0129 and U1104 are not output A
      DTC U0100, U0122, U0125, U0126, U0129 or U1104 is output B

    Result: 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [02/2017 - 10/2017]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2017 - 05/2018]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [05/2018 - 09/2019] 

    Result: 

    GO TO CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [02/2017 - 05/2018]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [05/2018 - 09/2019]