VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1439, C1445

DTC Code DTC Name
C1439 Steering Angle Sensor Initialization Incomplete
C1445 Vehicle Driven with Steering Angle Sensor not Initialized

DESCRIPTION

The skid control ECU (brake actuator assembly) acquires steering angle sensor zero point every time the engine switch is turned on (IG) and the vehicle is driven at 35 km/h (22 mph) or more for approximately 5 seconds. The ECU also stores previous zero points.

The steering angle sensor zero point malfunction warning is canceled by turning the engine switch off.

DTC No. DTC Detection Condition Trouble Area
C1439 After the steering angle sensor zero point calibration is cleared due to, for example, fluctuations in the power source, the steering angle sensor zero point calibration cannot be obtained for 0.048 seconds of continuous driving.

  • Steering angle sensor

  • Yaw rate and acceleration sensor (airbag sensor assembly)
C1445 Steering angle sensor zero point calibration cannot be obtained when the vehicle is driven without a record of steering angle sensor zero point calibration at a speed of 35 km/h (22 mph) or more for 30 seconds or more without the brake pedal being depressed.

  • Steering angle sensor

  • Yaw rate and acceleration sensor (airbag sensor assembly)

CAUTION / NOTICE / HINT

Note

Before proceeding with the inspection, explain to the customer that the output DTC is related to temporary loss of the steering angle zero point calibration, such as when the power voltage drops when the battery is removed, and confirm that this condition occurred.

Tech Tips


  • When U0073, U0124 and/or U0126 is output together with C1439 and/or C1445, inspect and repair the trouble areas indicated by U0073, U0124 and/or U0126 first Click here.

  • When a speed sensor or the yaw rate and acceleration sensor (airbag sensor assembly) has trouble, DTCs for the steering angle sensor may be stored even when the steering angle sensor is normal. When DTCs for the speed sensor or yaw rate and acceleration sensor (airbag sensor assembly) are output together with other DTCs for the steering angle sensor, inspect and repair the speed sensor and yaw rate and acceleration sensor (airbag sensor assembly) first, and then inspect and repair the steering angle sensor.

PROCEDURE


  1. CHECK DTC


    1. Clear the DTCs Click here.

    2. Turn the engine switch off.

    3. Turn the engine switch on (IG) again and check that no CAN communication system DTCs are output (See page for with Central Gateway ECU, Click here for without Central Gateway ECU).

    4. Drive the vehicle at a speed of 35 km/h (22 mph) or more and turn the steering wheel to the right and left and check that no speed sensor or yaw rate and acceleration sensor DTCs are output Click here.

      Result
      Result Proceed to
      DTCs C1439 and/or C1445 are output. A
      CAN communication system DTCs are output (w/ Central Gateway ECU). B
      CAN communication system DTCs are output (w/o Central Gateway ECU). C
      Speed sensor, yaw rate and acceleration sensor and/or steering angle sensor DTCs are output. D
      DTCs C1439 and C1445 are not output. E

      Tech Tips


      • If there is a malfunction in the speed sensor or the yaw rate and acceleration sensor (airbag sensor assembly), an abnormal value may be output although the steering angle sensor is normal.

      • If the speed sensor and the yaw rate and acceleration sensor (airbag sensor assembly) DTCs are output simultaneously, repair the sensors and inspect the steering angle sensor.

      • If DTC C1439 or C1445 is not output again, the DTC may have been stored due to a temporary loss of the steering angle zero point calibration, such as when the power voltage drops.


    B

    INSPECT CAN COMMUNICATION SYSTEM Click here

    C

    INSPECT CAN COMMUNICATION SYSTEM Click here

    D

    REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Click here

    E

    USE SIMULATION METHOD TO CHECK Click here

    A

  2. PERFORM STEERING ANGLE SENSOR ZERO POINT CALIBRATION


    1. Drive the vehicle straight ahead at 35 km/h (22 mph) or more for at least 5 seconds.

    2. Check that the centered position of the steering wheel is correctly set while driving straight ahead.

      Tech Tips

      If the front wheel alignment and steering position are adjusted as a result of an abnormal centered position of the steering wheel, acquire the yaw rate and acceleration sensor zero point again after the adjustments are completed.

      OK
      The centered position of the steering wheel is correctly set.

    NG

    ADJUST FRONT WHEEL ALIGNMENT OR STEERING POSITION Click here

    OK

  3. RECONFIRM DTC


    1. Turn the engine switch off.

    2. Clear the DTCs Click here.

    3. Turn the engine switch off.

    4. Start the engine.

    5. Drive the vehicle at a speed of 35 km/h (22 mph) or more and turn the steering wheel to the right and left.

    6. Check if the same DTC is output Click here.

      Result
      Result Proceed to
      DTCs C1439 and C1445 are not output. A
      Yaw rate and acceleration sensor and/or steering angle sensor DTCs are output. B

      Tech Tips

      If DTC C1439 or C1445 is not output again, the DTC may have been stored due to a temporary loss of the steering angle zero point calibration, such as when the power voltage drops.


    A

    END

    B

    REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Click here