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DTC C1A4A: Skid Control Buzzer Circuit [08/2017 - 08/2019]: Procedure

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

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

    2. Perform the Active Test according to the display on the Techstream.

      Refer to DATA LIST / ACTIVE TEST [08/2017 - 08/2019]

      NOTE:

      Perform the Active Test for 1 second or more.

      HINT: 

      Performing the Active Test for 1 second or more causes DTC C1A4A to be stored if the DTC detection conditions are met.

      BODY ELECTRICAL > PRE-COLLISION 2 > DATA LIST

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      PCS Crash Alarm Buzzer Skid control buzzer status ON or OFF ON: Skid control buzzer sounding
      OFF: Skid control buzzer not sounding      		 -
    3. Check for DTCs.

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

      Result

      Result Proceed to
      DTC C1A4A is not output A
      DTC C1A4A is output B

    Result: 

    A 

    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: 

    B 

    See step  2

  2. CHECK TERMINAL VOLTAGE 
    1. Disconnect the H135 skid control buzzer connector.
      GTY749643Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Skid Control Buzzer)
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      H135-2 (IG1) - Body ground Ignition switch ON 11 to 14 V
      Ignition switch off Below 1 V
    3. Connect the H135 skid control buzzer connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL BUZZER - BATTERY) 

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (SKID CONTROL BUZZER - FORWARD RECOGNITION CAMERA) 
    1. Disconnect the H135 skid control buzzer connector.
    2. Disconnect the U22 forward recognition camera connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      H135-1 (BZ) - U22-8 (BZ) Always Below 1 Ω
      H135-1 (BZ) or U22-8 (BZ) - Body ground Always 10 kΩ or higher
    4. Connect the U22 forward recognition camera connector.
    5. Connect the H135 skid control buzzer connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    See step  6

    Result: 

    NG 

    See step  4

  4. REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL BUZZER - FORWARD RECOGNITION CAMERA) 
    1. Repair or replace the harness or connector.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  5

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

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

    2. Perform the Active Test according to the display on the Techstream.

      Refer to DATA LIST / ACTIVE TEST [08/2017 - 08/2019]

      NOTE:

      Perform the Active Test for 1 second or more.

      HINT: 

      Performing the Active Test for 1 second or more causes DTC C1A4A to be stored if the DTC detection conditions are met.

      BODY ELECTRICAL > PRE-COLLISION 2 > DATA LIST

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      PCS Crash Alarm Buzzer Skid control buzzer status ON or OFF ON: Skid control buzzer sounding
      OFF: Skid control buzzer not sounding      		 -
    3. Check for DTCs.

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

      Result

      Result Proceed to
      DTC C1A4A is not output A
      DTC C1A4A is output B

    Result: 

    A 

    END 

    Result: 

    B 

    See step  6

  6. INSPECT SKID CONTROL BUZZER (CONFIRM BUZZER OPERATION) 
    1. Turn the ignition switch to ON.
    2. Check if the skid control buzzer is sounding.

      Result

      Result Proceed to
      The skid control buzzer does not sound when the ignition switch is ON A
      The skid control buzzer sounds continuously when the ignition switch is ON B

    Result: 

    B 

    See step  8

    Result: 

    A 

    See step  7

  7. INSPECT SKID CONTROL BUZZER (UNIT INSPECTION) 
    1. Remove the skid control buzzer.

      Refer to REMOVAL [08/2017 - ]

    2. Inspect the skid control buzzer.

      Refer to INSPECTION [08/2017 - ]

      Result

      Result Proceed to
      Skid control buzzer is abnormal A
      Skid control buzzer is normal B

    Result: 

    B 

    See step  9

    Result: 

    A 

    See step  8

  8. REPLACE SKID CONTROL BUZZER 
    1. Replace the skid control buzzer.

      Refer to REMOVAL [08/2017 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  9

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

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

    2. Perform the Active Test according to the display on the Techstream.

      Refer to DATA LIST / ACTIVE TEST [08/2017 - 08/2019]

      NOTE:

      Perform the Active Test for 1 second or more.

      HINT: 

      Performing the Active Test for 1 second or more causes DTC C1A4A to be stored if the DTC detection conditions are met.

      BODY ELECTRICAL > PRE-COLLISION 2 > DATA LIST

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      PCS Crash Alarm Buzzer Skid control buzzer status ON or OFF ON: Skid control buzzer sounding
      OFF: Skid control buzzer not sounding      		 -
    3. Check for DTCs.

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

      Result

      Result Proceed to
      DTC C1A4A is not output A
      DTC C1A4A is output B

    Result: 

    A 

    END 

    Result: 

    B 

    See step  10

  10. REPLACE FORWARD RECOGNITION CAMERA 
    1. Replace the forward recognition camera.

      Refer to REMOVAL [08/2017 - ]

    2. Perform forward recognition axis adjustment.

      Refer to ADJUSTMENT (SEQUENTIAL RECOGNITION) [08/2017 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  11

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

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

    2. Perform the Active Test according to the display on the Techstream.

      Refer to DATA LIST / ACTIVE TEST [08/2017 - 08/2019]

      NOTE:

      Perform the Active Test for 1 second or more.

      HINT: 

      Performing the Active Test for 1 second or more causes DTC C1A4A to be stored if the DTC detection conditions are met.

      BODY ELECTRICAL > PRE-COLLISION 2 > DATA LIST

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      PCS Crash Alarm Buzzer Skid control buzzer status ON or OFF ON: Skid control buzzer sounding
      OFF: Skid control buzzer not sounding      		 -
    3. Check for DTCs.

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

      Result

      Result Proceed to
      DTC C1A4A is not output A
      DTC C1A4A is output B

    Result: 

    A 

    END (FORWARD RECOGNITION CAMERA WAS DEFECTIVE) 

    Result: 

    B 

    See step  12

  12. REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY 
    1. Replace the millimeter wave radar sensor assembly.

      Refer to REMOVAL [08/2017 - ]

    2. Adjust the millimeter wave radar sensor assembly.

      Refer to ADJUSTMENT [08/2017 - 08/2018] , or refer to ADJUSTMENT [08/2018 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  13

  13. CLEAR DTC (PRE-COLLISION SYSTEM) 
    1. Clear the DTCs.

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

      Body Electrical > Pre-Collision 2 > Clear DTCs 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    END (MILLIMETER WAVE RADAR SENSOR ASSEMBLY WAS DEFECTIVE) 

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