PRE-CRASH SAFETY SYSTEM, Diagnostic DTC:C1A4A

DTC Code DTC Name
C1A4A Skid Control Buzzer Circuit

DESCRIPTION

The driving support ECU assembly operates the pre-crash warning by sending a buzzer request signal to the skid control buzzer.

If the driving support ECU assembly detects a malfunction in the skid control buzzer circuit, it will store DTC C1A4A.

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

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


  • A buzzer request signal is sent to the skid control buzzer but the buzzer does not sound for 1 second or more.

  • A buzzer request signal is not sent to the skid control buzzer but the buzzer sounds for 1 second or more.

  • Skid control buzzer

  • Driving support ECU assembly

  • Wire harness or connector

WIRING DIAGRAM

B004PM9E67
*a from IG1-NO. 1 Relay
*b ECU-IG1 NO. 4
*c Skid Control 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. CLEAR DTC


    1. Clear the DTCs.


      Body Electrical > Pre-Crash 2 > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  2. PERFORM ACTIVE TEST


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

      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-Crash 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-Crash 2 > Active Test
      Tester Display
      PCS Crash Alarm Buzzer
      Result
      Proceed to
      NEXT

    NEXT

  3. CHECK FOR DTCs (PRE-CRASH SAFETY SYSTEM)


    1. Check for DTCs.


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

    A

    USE SIMULATION METHOD TO CHECK Click here

    B

  4. CHECK TERMINAL VOLTAGE


    1. Disconnect the F41 skid control buzzer connector.

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

      Standard Voltage
      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

    NG

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

    OK

  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
      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

    OK

    GO TO STEP 10 Click here

    NG

  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

    NEXT

  7. CLEAR DTC


    1. Clear the DTCs.


      Body Electrical > Pre-Crash 2 > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  8. PERFORM ACTIVE TEST


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

      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-Crash 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-Crash 2 > Active Test
      Tester Display
      PCS Crash Alarm Buzzer
      Result
      Proceed to
      NEXT

    NEXT

  9. CHECK FOR DTCs (PRE-CRASH SAFETY SYSTEM)


    1. Check for DTCs.


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

    A

    END

    B

  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

    B

    GO TO STEP 12 Click here

    A

  11. INSPECT SKID CONTROL BUZZER (UNIT INSPECTION)


    1. Remove the skid control buzzer.

      Tech Tips

      Click here

    2. Inspect the skid control buzzer.

      Click here

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

    B

    GO TO STEP 13 Click here

    A

  12. REPLACE SKID CONTROL BUZZER


    1. Replace the skid control buzzer.

      Tech Tips

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  13. CLEAR DTC


    1. Clear the DTCs.


      Body Electrical > Pre-Crash 2 > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  14. PERFORM ACTIVE TEST


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

      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-Crash 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-Crash 2 > Active Test
      Tester Display
      PCS Crash Alarm Buzzer
      Result
      Proceed to
      NEXT

    NEXT

  15. CHECK FOR DTCs (PRE-CRASH SAFETY SYSTEM)


    1. Check for DTCs.


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

    A

    END

    B

    REPLACE DRIVING SUPPORT ECU ASSEMBLY Click here