PRE-COLLISION SYSTEM, Diagnostic DTC:C1AA3

DTC Code DTC Name
C1AA3 Vehicle Speed Sensor Circuit

DESCRIPTION

The pre-collision city sensor receives vehicle speed signals from the brake actuator assembly (skid control ECU). When the brake actuator assembly (skid control ECU) detects a malfunction in a wheel speed sensor, the pre-collision city sensor is notified via CAN communication and DTC C1AA3 is stored.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

C1AA3

Vehicle Speed Sensor Circuit

While the system is operating, a wheel speed sensor malfunction signal is continuously received for 1 second or more from the brake actuator assembly (skid control ECU).

  • Vehicle stability control system

  • Brake actuator assembly (skid control ECU)

  • Pre-collision city sensor

CAUTION / NOTICE / HINT

Note:

  • When replacing the pre-collision city sensor, replace it with a new one and be sure to initialize the settings. If a pre-collision city sensor which was installed to another vehicle is used, the information stored in the pre-collision city sensor will not match the information from the vehicle and, as a result, a DTC may be stored.

  • If the pre-collision city sensor has been replaced, or the windshield glass has been replaced or removed/installed, be sure to perform Pre-collision City Sensor Optical Axis Learning.

    Tip:

    Pre-collision City Sensor Optical Axis Learning can be performed by using either One Time Recognition or Sequential Recognition.

    One Time Recognition:Click here

    Sequential Recognition:Click here

  • First check the CAN communication system by following How to Proceed with Troubleshooting. After checking that there are no malfunctions in the CAN communication system, proceed with troubleshooting.

    Click here

PROCEDURE

  1. CHECK FOR DTCS (VEHICLE STABILITY CONTROL SYSTEM)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Chassis / ABS/VSC/TRC / Trouble Codes.

    5. Check for DTCs.

      Click here

      Chassis > ABS/VSC/TRC > Trouble Codes

    Result

    Result

    Proceed to

    Vehicle stability control system DTCs are not output

    A

    Vehicle stability control system DTCs are output

    B
    B

    GO TO VEHICLE STABILITY CONTROL SYSTEM

    Click here

    A

  2. CHECK FOR DTCS

    1. Clear the DTCs.

      Click here

      Chassis > PCS/LDA/RSA/LVN > Clear DTCs

    2. Make sure that the DTC detection conditions are met.

      Tip:

      If the detection conditions are not met, the system cannot detect the malfunction.

    3. Check for DTCs.

      Click here

      Chassis > PCS/LDA/RSA/LVN > Trouble Codes

    Result

    Result

    Proceed to

    DTC C1AA3 is not output

    A

    DTC C1AA3 is output

    B
    A

    USE SIMULATION METHOD TO CHECK

    Click here

    B

  3. REPLACE PRE-COLLISION CITY SENSOR

    1. Replace the pre-collision city sensor.

      Click here

    2. Perform Pre-collision City Sensor Optical Axis Learning.

      Tip:

      Pre-collision City Sensor Optical Axis Learning can be performed by using either One Time Recognition or Sequential Recognition.

      One Time Recognition:Click here

      Sequential Recognition:Click here

    Result

    Proceed to

    NEXT
    NEXT

  4. CHECK FOR DTCS

    1. Clear the DTCs.

      Click here

      Chassis > PCS/LDA/RSA/LVN > Clear DTCs

    2. Make sure that the DTC detection conditions are met.

      Tip:

      If the detection conditions are not met, the system cannot detect the malfunction.

    3. Check for DTCs.

      Click here

      Chassis > PCS/LDA/RSA/LVN > Trouble Codes

    Result

    Result

    Proceed to

    DTC C1AA3 is not output

    A

    DTC C1AA3 is output

    B
    A

    END (PRE-COLLISION CITY SENSOR WAS DEFECTIVE)

    B

    REPLACE BRAKE ACTUATOR ASSEMBLY (SKID CONTROL ECU)

    Click here