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DTC C1A4A: Skid Control Buzzer Circuit [08/2015 - ]: 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 [08/2015 - ] ).
    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 Pre-collision city buzzer ON/OFF Test possible with engine switch on (IG), vehicle stopped
    8. Check for DTCs (Refer to DTC CHECK / CLEAR [08/2015 - ] ).
      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 [08/2015 - 08/2017] , or refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2017 - ] )

    Result: 

    A 

    See step  2

  2. CHECK TERMINAL VOLTAGE 
    1. Disconnect the pre-collision city buzzer connector.
      GTY564334Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Pre-collision City Buzzer)
    2. Measure the voltage according to the value(s) in the table below.
      STANDARD VOLTAGE :

      Tester Connection Condition Specified Condition
      E96-2 (IG1) - Body ground Engine switch on (IG) 11 to 14 V
      E96-2 (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 (PRE-COLLISION CITY BUZZER - DRIVING SUPPORT ECU ASSEMBLY) 
    1. Disconnect the pre-collision city 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
      E96-1 (BZ) - E117-3 (BZ) Always Below 1 Ω
      E96-1 (BZ) orE1178-3 (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 [08/2015 - ] ).
    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 Pre-collision city buzzer ON/OFF Test possible with engine switch on (IG), vehicle stopped
    8. Check for DTCs (Refer to DTC CHECK / CLEAR [08/2015 - ] ).
      RESULT

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

    Result: 

    B 

    END (PRE-COLLISION CITY BUZZER WAS DEFECTIVE) 

    Result: 

    A 

    See step  6

  6. INSPECT PRE-COLLISION CITY BUZZER (CONFIRM BUZZER OPERATION) 
    1. Turn the engine switch on (IG).
    2. Check if the pre-collision city buzzer is sounding.
      RESULT

      Result Proceed to
      The pre-collision city buzzer does not sound when the engine switch is on (IG). A
      The pre-collision city buzzer sounds continuously when the engine switch is on (IG). B

    Result: 

    B 

    See step  8

    Result: 

    A 

    See step  7

  7. INSPECT PRE-COLLISION CITY BUZZER (UNIT INSPECTION) 
    1. Remove the pre-collision city buzzer (Refer to REMOVAL [08/2015 - ] ).
    2. Inspect the pre-collision city buzzer (Refer to INSPECTION [08/2015 - ] ).
      RESULT

      Result Proceed to
      Pre-collision city buzzer is abnormal. A
      Pre-collision city buzzer is normal. B

    Result: 

    B 

    See step  9

    Result: 

    A 

    See step  8

  8. REPLACE PRE-COLLISION CITY BUZZER 
    1. Replace the pre-collision city buzzer (Refer to REMOVAL [08/2015 - ] ).

    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 [08/2015 - ] ).
    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 [08/2015 - ] ).
      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 [08/2015 - ] )

    Result: 

    B 

    END (PRE-COLLISION CITY BUZZER WAS DEFECTIVE) 

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