LANE DEPARTURE ALERT SYSTEM, Diagnostic DTC:C1AA3

DTC Code DTC Name
C1AA3 Vehicle Speed Sensor Circuit

DESCRIPTION

The pre-crash safety city sensor receives vehicle speed signals from the brake booster with master cylinder assembly (skid control ECU). When the brake booster with master cylinder assembly (skid control ECU) detects a malfunction in the vehicle wheel speed sensor, the pre-crash safety city sensor is notified via CAN communication and DTC C1AA3 is output.

DTC Code DTC Detection Condition Trouble Area
C1AA3 While the system is operating, a vehicle wheel speed sensor malfunction signal is continuously received for 5 seconds or more from the brake booster with master cylinder assembly (skid control ECU).

  • Electronically controlled brake system

  • Brake booster with master cylinder assembly (skid control ECU)

  • Pre-crash safety city sensor

CAUTION / NOTICE / HINT

Note


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

  • If the pre-crash safety city sensor has been replaced, or the windshield glass has been replaced or removed/installed, be sure to perform Recognition Camera/Target Position Memory and Recognition Camera Axis Adjust.

  • Perform adjustment using "ONE TIME RECOGNITION" or "SEQUENTIAL RECOGNITION".


  • 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 to troubleshooting.

PROCEDURE


  1. CHECK FOR DTC (ELECTRONICALLY CONTROLLED BRAKE SYSTEM)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON (IG).

    3. Turn the GTS on.

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

    5. Check for DTCs Click here.

      Result
      Result Proceed to
      Electronically controlled brake system DTCs are not output A
      Electronically controlled brake system DTCs are output B

    B

    GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM Click here

    A

  2. CHECK FOR DTC


    1. Clear the DTCs Click here.

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

      Tech Tips

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

    3. Check for DTCs Click here.

      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-CRASH SAFETY CITY SENSOR


    1. Replace the pre-crash safety city sensor with a new one Click here.

    2. Perform pre-crash safety city sensor beam axis learning.


      • Perform adjustment using "ONE TIME RECOGNITION" or "SEQUENTIAL RECOGNITION".



    NEXT

  4. CHECK FOR DTC


    1. Clear the DTCs Click here.

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

      Tech Tips

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

    3. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC C1AA3 is not output A
      DTC C1AA3 is output (for LHD) B
      DTC C1AA3 is output (for RHD) C

    A

    END (PRE-CRASH SAFETY CITY SENSOR WAS DEFECTIVE)

    B

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY (SKID CONTROL ECU) Click here

    C

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY (SKID CONTROL ECU) Click here