PRE-COLLISION SYSTEM, Diagnostic DTC:C1A4A

DTC Code DTC Name
C1A4A Skid Control Buzzer Circuit

DESCRIPTION

The driving support ECU assembly operates the pre-collision warning by sending a buzzer request signal to the pre-collision city buzzer.

If the driving support ECU assembly detects a malfunction in the pre-collision city buzzer circuit, it will store DTC C1A4A.

DTC No. Detection Item DTC Detection Condition Trouble Area
C1A4A Skid Control Buzzer Circuit

When the engine switch is on (IG) and the pre-collision warning is operating, either of the following conditions is met:


  • A buzzer request signal is sent to the pre-collision city buzzer but the buzzer does not sound for 1 second or more.

  • A buzzer request signal is not sent to the pre-collision city buzzer but the buzzer sounds for 1 second or more.

  • Pre-collision city buzzer

  • Driving support ECU assembly

  • Wire harness or connector

WIRING DIAGRAM

B000UVLE05
*a from IG Circuit
*b IG1 D NO.2
*c Pre-collision City Buzzer
*d Driving Support ECU Assembly

CAUTION / NOTICE / HINT

Note


  • Inspect the fuses for circuits related to this system before performing the following procedure.

  • When replacing the driving support ECU assembly, always replace it with a new one. If a driving support ECU assembly which was installed to another vehicle is used, the information stored in the driving support ECU assembly will not match the information from the vehicle. As a result, a DTC may be stored.

PROCEDURE


  1. CHECK FOR DTCs (PRE-COLLISION SYSTEM)


    1. Clear the DTCs.

      Click here


      Body Electrical > Pre-Collision 2 > Clear DTCs

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

      Click here

      Note

      Perform the Active Test for 1 second or more.

      Tech Tips

      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 Collision Alarm Buzzer Pre-collision city buzzer ON / OFF Test possible with engine switch on (IG), vehicle stopped

      Body Electrical > Pre-Collision 2 > Active Test
      Tester Display
      PCS Collision Alarm Buzzer

    3. Check for DTCs.

      Click here


      Body Electrical > Pre-Collision 2 > Trouble Codes
      Result
      Result Proceed to
      DTC C1A4A is not output A
      DTC C1A4A is output B

    A

    USE SIMULATION METHOD TO CHECK Click here

    B

  2. CHECK TERMINAL VOLTAGE


    1. B000Z39C16
      *a

      Front view of wire harness connector

      (to Pre-collision City Buzzer)

      Disconnect the P61 pre-collision city buzzer connector.

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      P61-2 (IG1) - Body ground Engine switch on (IG) 11 to 14 V
      Engine switch off Below 1 V

    3. Connect the P61 pre-collision city buzzer connector.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (PRE-COLLISION CITY BUZZER - BATTERY)

    OK

  3. CHECK HARNESS AND CONNECTOR (PRE-COLLISION CITY BUZZER - DRIVING SUPPORT ECU ASSEMBLY)


    1. Disconnect the P61 pre-collision city buzzer connector.

    2. Disconnect the P62 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
      P61-1 (BZ) - P62-3 (BZ) Always Below 1 Ω
      P61-1 (BZ) or P62-3 (BZ) - Body ground Always 10 kΩ or higher

    4. Connect the P62 driving support ECU assembly connector.

    5. Connect the P61 pre-collision city buzzer connector.

      Result
      Proceed to
      OK
      NG

    OK

    GO TO STEP 6 Click here

    NG

  4. REPAIR OR REPLACE HARNESS OR CONNECTOR (PRE-COLLISION CITY BUZZER - DRIVING SUPPORT ECU ASSEMBLY)


    1. Repair or replace the harness or connector.

      Result
      Proceed to
      NEXT

    NEXT

  5. CHECK FOR DTCs (PRE-COLLISION SYSTEM)


    1. Clear the DTCs.

      Click here


      Body Electrical > Pre-Collision 2 > Clear DTCs

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

      Click here

      Note

      Perform the Active Test for 1 second or more.

      Tech Tips

      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 Collision Alarm Buzzer Pre-collision city buzzer ON / OFF Test possible with engine switch on (IG), vehicle stopped

      Body Electrical > Pre-Collision 2 > Active Test
      Tester Display
      PCS Collision Alarm Buzzer

    3. Check for DTCs.

      Click here


      Body Electrical > Pre-Collision 2 > Trouble Codes
      Result
      Result Proceed to
      DTC C1A4A is not output A
      DTC C1A4A is output B

    A

    END

    B

  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

    B

    GO TO STEP 8 Click here

    A

  7. INSPECT PRE-COLLISION CITY BUZZER (UNIT INSPECTION)


    1. Remove the pre-collision city buzzer.

      Click here

    2. Inspect the pre-collision city buzzer.

      Click here

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

    B

    GO TO STEP 9 Click here

    A

  8. REPLACE PRE-COLLISION CITY BUZZER


    1. Replace the pre-collision city buzzer.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  9. CHECK FOR DTCs (PRE-COLLISION SYSTEM)


    1. Clear the DTCs.

      Click here


      Body Electrical > Pre-Collision 2 > Clear DTCs

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

      Click here

      Note

      Perform the Active Test for 1 second or more.

      Tech Tips

      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 Collision Alarm Buzzer Pre-collision city buzzer ON / OFF Test possible with engine switch on (IG), vehicle stopped

      Body Electrical > Pre-Collision 2 > Active Test
      Tester Display
      PCS Collision Alarm Buzzer

    3. Check for DTCs.

      Click here


      Body Electrical > Pre-Collision 2 > Trouble Codes
      Result
      Result Proceed to
      DTC C1A4A is not output A
      DTC C1A4A is output B

    A

    END

    B

    REPLACE DRIVING SUPPORT ECU ASSEMBLY Click here