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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 U0104: Lost Communication with Cruise Control Module; DTC U0122: Lost Communication with Vehicle Dynamics Control Module [08/2020 - ] >> Procedure
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DTC U0100: Lost Communication with ECM / PCM "A"; DTC U0104: Lost Communication with Cruise Control Module; DTC U0122: Lost Communication with Vehicle Dynamics Control Module [08/2020 - ]: Procedure

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

      Powertrain > Radar Cruise 1 > 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.

    3. Check for DTCs.

      Powertrain > Radar Cruise 1 > Trouble Codes 

      Result

      Result Proceed to
      DTC U0100, U0104 and U0122 are not output A
      DTC U0100, U0104 or U0122 is output B

    Result: 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2020 - ] 

    Result: 

    GO TO CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2020 - ]