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DTC C1A52: Driving Support ECU Communication Abnormal [11/2017 - 01/2023]: Procedure

  1. CHECK FOR DTCs 
    1. Clear the DTCs.

      Powertrain > Radar Cruise > Clear DTCs 

    2. Perform the following to make sure that the DTC detection conditions are met.

      HINT: 

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

      1. Turn the engine switch on (IG).
      2. Wait for 20 seconds or more.
    3. Check for DTCs.

      Powertrain > Radar Cruise > Trouble Codes 

      Result

      Result Proceed to
      DTC C1A52 is not output A
      DTC C1A52 is output B

    Result: 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2017 - 03/2019]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [03/2019 - 09/2020]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [09/2020 - 01/2023] 

    Result: 

    See step  2

  2. REPLACE ECM 
    1. Replace the ECM with a new one.

      Refer to REMOVAL [09/2014 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  3

  3. CHECK FOR DTCs 
    1. Clear the DTCs.

      Powertrain > Radar Cruise > Clear DTCs 

    2. Perform the following to make sure that the DTC detection conditions are met.

      HINT: 

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

      1. Turn the engine switch on (IG).
      2. Wait for 20 seconds or more.
    3. Check for DTCs.

      Powertrain > Radar Cruise > Trouble Codes 

      Result

      Result Proceed to
      DTC C1A52 is not output A
      DTC C1A52 is output B

    Result: 

    END (ECM WAS DEFECTIVE) 

    Result: 

    REPLACE DRIVING SUPPORT ECU ASSEMBLY. Refer to  COMPONENTS [09/2014 - 01/2023]