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DTC C1A4B: Stop Light Relay Circuit [08/2017 - 08/2019]: Procedure

  1. CHECK FOR DTCs (VEHICLE STABILITY CONTROL SYSTEM) 

    HINT: 

    Pre-collision system DTC C1A4B may be stored due to a malfunction in the vehicle stability control system. Therefore, it is necessary to check for and troubleshoot vehicle stability control system DTCs first.

    1. Check for DTCs.

      Refer to DTC CHECK / CLEAR [08/2017 - 08/2019]

      Result

      Result Proceed to
      Vehicle stability control system DTCs are not output A
      Vehicle stability control system DTCs are output B

    Result: 

    GO TO VEHICLE STABILITY CONTROL SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2017 - ] 

    Result: 

    See step  2

  2. CHECK FOR DTCs (PRE-COLLISION SYSTEM) 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [08/2017 - 08/2019]

    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.

      Refer to DTC CHECK / CLEAR [08/2017 - 08/2019]

      Result

      Result Proceed to
      DTC C1A4B is not output A
      DTC C1A4B is output B

    Result: 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2017 - 08/2018]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2018 - 08/2019] 

    Result: 

    REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY. Refer to  REMOVAL [08/2017 - ]