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DTC C1A4A: Skid Control Buzzer Circuit [09/2015 - ]: Procedure

  1. CHECK DTC OUTPUT (PRE-COLLISION SYSTEM) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Pre-Collision 2 / Trouble Codes.
    5. Clear the DTCs. Refer to DTC CHECK / CLEAR [09/2015 - ] .
    6. Enter the following menus: Body Electrical / Pre-Collision 2 / Active Test.
    7. Perform the Active Test according to the display on the Techstream.
      NOTE:

      Perform the Active Test for 1 second or more.

      HINT: 

      This DTC can be stored by performing the Active Test.

      PRE-COLLISION 2

      Tester Display Test Part Control Range Diagnostic Note
      PCS Crash Alarm Buzzer Skid control buzzer ON/OFF Test possible with engine switch on (IG), vehicle stopped
    8. Check for DTCs. Refer to DTC CHECK / CLEAR [09/2015 - ] .
      RESULT

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

    Result: 

    B 

    USE SIMULATION METHOD TO CHECK (SYMPTOM SIMULATION) 

    Refer to HOW TO PROCEED WITH TROUBLESHOOTING [09/2015 - ] )

    Result: 

    A 

    See step  2

  2. CHECK TERMINAL VOLTAGE 
    1. Disconnect the skid control buzzer connector.
      GTY669252Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      * 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 Condition Specified Condition
      E5-2 (IG1) - Body ground Engine switch on (IG) 11 to 14 V
      E5-2 (IG1) - Body ground Engine switch off Below 1 V

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (SKID CONTROL BUZZER - DRIVING SUPPORT ECU ASSEMBLY) 
    1. Disconnect the skid control buzzer connector.
    2. Disconnect the 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
      E5-1 (BZ) - E138-3 (BZ) Always Below 1 Ω
      E5-1 (BZ) orE138-3 (BZ) - Body ground Always 10 kΩ or higher
      RESULT

      Result Proceed to
      NG A
      OK B

    Result: 

    B 

    See step  6

    Result: 

    A 

    See step  4

  4. REPAIR OR REPLACE HARNESS OR CONNECTOR 
    1. Repair or replace the harness or connector.

    Result: 

    NEXT 

    See step  5

  5. CHECK DTC OUTPUT (PRE-COLLISION SYSTEM) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Pre-Collision 2 / Trouble Codes.
    5. Clear the DTCs. Refer to DTC CHECK / CLEAR [09/2015 - ] .
    6. Enter the following menus: Body Electrical / Pre-Collision 2 / Active Test.
    7. Perform "Active Test" according to the display on the Techstream.
      NOTE:

      Perform the Active Test for 1 second or more.

      HINT: 

      This DTC can be stored by performing the Active Test.

      PRE-COLLISION 2

      Tester Display Test Part Control Range Diagnostic Note
      PCS Crash Alarm Buzzer Skid control buzzer ON/OFF Test possible with engine switch on (IG), vehicle stopped
    8. Check for DTCs. Refer to DTC CHECK / CLEAR [09/2015 - ] .
      RESULT

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

    Result: 

    B 

    END (SKID CONTROL BUZZER WAS DEFECTIVE) 

    Result: 

    A 

    See step  6

  6. INSPECT SKID CONTROL BUZZER (CONFIRM BUZZER OPERATION) 
    1. Turn the engine switch on (IG).
    2. Check if the skid control buzzer is sounding.
      RESULT

      Result Proceed to
      The skid control buzzer does not sound when the engine switch is on (IG). A
      The skid control buzzer 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 (UNIT INSPECTION) 
    1. Remove the skid control buzzer. Refer to REMOVAL [09/2015 - ] .
    2. Inspect the skid control buzzer. Refer to INSTALLATION [09/2015 - ] .
      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 [09/2015 - ] .

    Result: 

    NEXT 

    See step  9

  9. CHECK DTC OUTPUT (PRE-COLLISION SYSTEM) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Pre-Collision 2 / Trouble Codes.
    5. Clear the DTCs. Refer to DTC CHECK / CLEAR [09/2015 - ] .
    6. Enter the following menus: Body Electrical / Pre-Collision 2 / Active Test.
    7. Perform "Active Test" according to the display on the Techstream.
      NOTE:

      Perform the Active Test for 1 second or more.

      HINT: 

      This DTC can be stored by performing the Active Test.

      PRE-COLLISION 2

      Tester Display Test Part Control Range Diagnostic Note
      PCS Crash Alarm Buzzer Sounds PCS Crash Alarm Buzzer ON/OFF Test possible with engine switch on (IG), vehicle stopped
    8. Check for DTCs. Refer to DTC CHECK / CLEAR [09/2015 - ] .
      RESULT

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

    Result: 

    A 

    REPLACE DRIVING SUPPORT ECU ASSEMBLY 

    Refer to REMOVAL [09/2015 - ] )

    Result: 

    B 

    END (SKID CONTROL BUZZER WAS DEFECTIVE) 

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