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 alarm control by sending a buzzer request signal to the skid control buzzer assembly.

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

DTC No. DTC Detection Condition Trouble Area
C1A4A

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


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

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

  • Skid control buzzer assembly

  • Driving support ECU assembly

  • Wire harness or connector

WIRING DIAGRAM

A000518E87
*a from IG1 NO.4 Relay
*b ECU-IG1 NO. 3
*c Skid Control Buzzer Assembly
*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 DTC OUTPUT (PRE-CRASH SAFETY SYSTEM)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Pre-Crash 2 / Trouble Codes.

    5. Clear the DTCs Click here.

    6. Enter the following menus: Body Electrical / Pre-Crash 2 / Active Test.

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

      Note

      Perform the Active Test for 1 second or more.

      Tech Tips

      This DTC can be stored by performing the Active Test.

      Pre-Crash 2
      Tester Display Test Part Control Range Diagnostic Note
      PCS Crash Alarm Buzzer Skid control buzzer assembly ON/OFF Test possible with power switch on (IG), vehicle stopped

    8. Check for DTCs Click here.

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

    B

    USE SIMULATION METHOD TO CHECK (SYMPTOM SIMULATION) Click here

    A

  2. CHECK TERMINAL VOLTAGE


    1. A00097BE01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Skid Control Buzzer Assembly)

      Disconnect the skid control buzzer assembly connector.

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

      Standard Voltage :
      Tester Connection Condition Specified Condition
      H65-2 (IG1) - Body ground Power switch on (IG) 11 to 14 V
      H65-2 (IG1) - Body ground Power switch off Below 1 V

    NG

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

    OK

  3. CHECK HARNESS AND CONNECTOR (SKID CONTROL BUZZER ASSEMBLY - DRIVING SUPPORT ECU ASSEMBLY)


    1. Disconnect the skid control buzzer assembly 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
      H65-1 (BZ) - H196-3 (BZ) Always Below 1 Ω
      H65-1 (BZ) or H196-3 (BZ) - Body ground Always 10 kΩ or higher
      Result
      Result Proceed to
      NG A
      OK B

    B

    INSPECT SKID CONTROL BUZZER ASSEMBLY (CONFIRM BUZZER OPERATION) Click here

    A

  4. REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL BUZZER ASSEMBLY - DRIVING SUPPORT ECU ASSEMBLY)


    1. Repair or replace the harness or connector.


    NEXT

  5. CHECK DTC OUTPUT (PRE-CRASH SAFETY SYSTEM)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Pre-Crash 2 / Trouble Codes.

    5. Clear the DTCs Click here.

    6. Enter the following menus: Body Electrical / Pre-Crash 2 / Active Test.

    7. Perform "Active Test" according to the display on the GTS.

      Note

      Perform the Active Test for 1 second or more.

      Tech Tips

      This DTC can be stored by performing the Active Test.

      Pre-Crash 2
      Tester Display Test Part Control Range Diagnostic Note
      PCS Crash Alarm Buzzer Skid control buzzer assembly ON/OFF Test possible with power switch on (IG), vehicle stopped

    8. Check for DTCs Click here.

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

    B

    END

    A

  6. INSPECT SKID CONTROL BUZZER ASSEMBLY (CONFIRM BUZZER OPERATION)


    1. Turn the power switch on (IG).

    2. Check if the skid control buzzer assembly is sounding.

      Result
      Result Proceed to
      The skid control buzzer assembly does not sound when the power switch is on (IG). A
      The skid control buzzer assembly sounds continuously when the power switch is on (IG). B

    B

    REPLACE SKID CONTROL BUZZER ASSEMBLY Click here

    A

  7. INSPECT SKID CONTROL BUZZER ASSEMBLY (UNIT INSPECTION)


    1. Remove the skid control buzzer assembly Click here.

    2. Inspect the skid control buzzer assembly Click here.

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

    B

    CHECK DTC OUTPUT (PRE-CRASH SAFETY SYSTEM) Click here

    A

  8. REPLACE SKID CONTROL BUZZER ASSEMBLY


    1. Replace the skid control buzzer assembly Click here.


    NEXT

  9. CHECK DTC OUTPUT (PRE-CRASH SAFETY SYSTEM)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Pre-Crash 2 / Trouble Codes.

    5. Clear the DTCs Click here.

    6. Enter the following menus: Body Electrical / Pre-Crash 2 / Active Test.

    7. Perform "Active Test" according to the display on the GTS.

      Note

      Perform the Active Test for 1 second or more.

      Tech Tips

      This DTC can be stored by performing the Active Test.

      Pre-Crash 2
      Tester Display Test Part Control Range Diagnostic Note
      PCS Crash Alarm Buzzer Sounds PCS Crash Alarm Buzzer ON/OFF Test possible with power switch on (IG), vehicle stopped

    8. Check for DTCs Click here.

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

    A

    REPLACE DRIVING SUPPORT ECU ASSEMBLY Click here

    B

    END