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DTC C1A4A: Skid Control Buzzer Circuit [11/2015 - 12/2018]: Procedure

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

      Body Electrical > Pre-Collision 2 > Clear DTCs 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  2

  2. PERFORM ACTIVE TEST USING TECHSTREAM 
    1. 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.

      Body Electrical > Pre-Collision 2 > Active Test 

      Tester Display Measurement Item Control Range Diagnostic Note
      PCS Crash Alarm Buzzer Skid control buzzer ON / OFF Test possible with power switch on (IG), vehicle stopped

      Body Electrical > Pre-Collision 2 > Active Test 

      Tester Display
      PCS Crash Alarm Buzzer

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  3

  3. CHECK FOR DTCs (PRE-COLLISION SYSTEM) 
    1. Check for DTCs.

      Body Electrical > Pre-Collision 2 > Trouble Codes 

      Result

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

    Result: 

    A 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2015 - 12/2018] 

    Result: 

    B 

    See step  4

  4. CHECK TERMINAL VOLTAGE 
    1. Disconnect the F41 skid control buzzer connector.
      GTY607147Courtesy 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

      (F41)

      (F41)

      Tester Connection Condition Specified Condition
      F41-2 (IG1) - Body ground Power switch on (IG) 11 to 14 V
      F41-2 (IG1) - Body ground Power switch off Below 1 V
    3. Connect the F41 skid control buzzer connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

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

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (SKID CONTROL BUZZER - DRIVING SUPPORT ECU ASSEMBLY) 
    1. Disconnect the F41 skid control buzzer connector.
    2. Disconnect the F40 driving support ECU assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      (F41, F40)

      (F41)

      (F40)

      Tester Connection Condition Specified Condition
      F41-1 (BZ) - F40-3 (BZ) Always Below 1 Ω
      F41-1 (BZ) or F40-3 (BZ) - Body ground Always 10 kΩ or higher
    4. Connect the F40 driving support ECU assembly connector.
    5. Connect the F41 skid control buzzer connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    See step  10

    Result: 

    NG 

    See step  6

  6. REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL BUZZER - DRIVING SUPPORT ECU ASSEMBLY) 
    1. Repair or replace the harness or connector.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  7

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

      Body Electrical > Pre-Collision 2 > Clear DTCs 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  8

  8. PERFORM ACTIVE TEST USING TECHSTREAM 
    1. 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.

      Body Electrical > Pre-Collision 2 > Active Test 

      Tester Display Measurement Item Control Range Diagnostic Note
      PCS Crash Alarm Buzzer Skid control buzzer ON / OFF Test possible with power switch on (IG), vehicle stopped

      Body Electrical > Pre-Collision 2 > Active Test 

      Tester Display
      PCS Crash Alarm Buzzer

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  9

  9. CHECK FOR DTCs (PRE-COLLISION SYSTEM) 
    1. Check for DTCs.

      Body Electrical > Pre-Collision 2 > Trouble Codes 

      Result

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

    Result: 

    A 

    END 

    Result: 

    B 

    See step  10

  10. INSPECT SKID CONTROL BUZZER (CONFIRM BUZZER OPERATION) 
    1. Turn the power 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 power switch is on (IG) A
      The skid control buzzer sounds continuously when the power switch is on (IG) B

    Result: 

    B 

    See step  12

    Result: 

    A 

    See step  11

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

      HINT: 

      Refer to REMOVAL [11/2015 - 12/2018]

    2. Inspect the skid control buzzer.

      Refer to INSPECTION [11/2015 - 12/2018]

      Result

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

    Result: 

    B 

    See step  15

    Result: 

    A 

    See step  12

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

      HINT: 

      Refer to REMOVAL [11/2015 - 12/2018]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  13

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

      Body Electrical > Pre-Collision 2 > Clear DTCs 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  14

  14. CHECK FOR DTCs (PRE-COLLISION SYSTEM) 
    1. 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.

      Body Electrical > Pre-Collision 2 > Active Test 

      Tester Display Measurement Item Control Range Diagnostic Note
      PCS Crash Alarm Buzzer Skid control buzzer ON / OFF Test possible with power switch on (IG), vehicle stopped

      Body Electrical > Pre-Collision 2 > Active Test 

      Tester Display
      PCS Crash Alarm Buzzer

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  15

  15. CHECK FOR DTCs (PRE-COLLISION SYSTEM) 
    1. Check for DTCs.

      Body Electrical > Pre-Collision 2 > Trouble Codes 

      Result

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

    Result: 

    A 

    END 

    Result: 

    B 

    REPLACE DRIVING SUPPORT ECU ASSEMBLY. Refer to  COMPONENTS [11/2015 - 07/2020] 

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