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DTC C1A4A: Skid Control Buzzer Circuit [10/2015 - ]: Procedure

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

      Refer to DTC CHECK / CLEAR [10/2015 - ]

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

      PRE-COLLISION 2

      Tester Display Test Part Control Range Diagnostic Note
      PCS Crash Alarm Buzzer Skid control buzzer assembly ON / OFF Test possible with engine switch on (IG), vehicle stopped
    3. Check for DTCs.

      Refer to DTC CHECK / CLEAR [10/2015 - ]

      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 [10/2015 - ] 

    Result: 

    B 

    See step  2

  2. CHECK TERMINAL VOLTAGE 
    1. Disconnect the skid control buzzer assembly connector.
      GTY652476Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Skid Control Buzzer Assembly)
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      N1-2 (IG1) - Body ground Engine switch on (IG) 11 to 14 V
      Engine switch off Below 1 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (SKID CONTROL BUZZER ASSEMBLY - DRIVING SUPPORT ECU ASSEMBLY) 
    1. Disconnect the N1 skid control buzzer assembly connector.
    2. Disconnect the N161 driving support ECU assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      N1-1 (BZ) - N161-3 (BZ) Always Below 1 Ω
      N1-1 (BZ) or N161-3 (BZ) - Body ground Always 10 kΩ or higher

      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 ASSEMBLY - DRIVING SUPPORT ECU ASSEMBLY) 
    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 [10/2015 - ]

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

      PRE-COLLISION 2

      Tester Display Test Part Control Range Diagnostic Note
      PCS Crash Alarm Buzzer Skid control buzzer assembly ON / OFF Test possible with engine switch on (IG), vehicle stopped
    3. Check for DTCs.

      Refer to DTC CHECK / CLEAR [10/2015 - ]

      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 ASSEMBLY (CONFIRM BUZZER OPERATION) 
    1. Turn the engine switch on (IG).
    2. Check if the skid control buzzer assembly is sounding.

      Result

      Result Proceed to
      The skid control buzzer assembly does not sound when the engine switch is on (IG) A
      The skid control buzzer assembly sounds continuously when the engine switch is on (IG) B

    Result: 

    B 

    See step  8

    Result: 

    A 

    See step  7

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

      Refer to REMOVAL [10/2015 - ]

    2. Inspect the skid control buzzer assembly.

      Refer to INSPECTION [10/2015 - ]

      Result

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

    Result: 

    B 

    See step  9

    Result: 

    A 

    See step  8

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

      Refer to REMOVAL [10/2015 - ]

      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 [10/2015 - ]

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

      PRE-COLLISION 2

      Tester Display Test Part Control Range Diagnostic Note
      PCS Crash Alarm Buzzer Skid control buzzer assembly ON / OFF Test possible with engine switch on (IG), vehicle stopped
    3. Check for DTCs.

      Refer to DTC CHECK / CLEAR [10/2015 - ]

      Result

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

    Result: 

    A 

    END (SKID CONTROL BUZZER ASSEMBLY WAS DEFECTIVE) 

    Result: 

    B 

    REPLACE DRIVING SUPPORT ECU ASSEMBLY. Refer to  REMOVAL [10/2015 - ] 

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