ELECTRONICALLY CONTROLLED BRAKE 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 assembly acquires the steering sensor zero point every time the power 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.

DTCs C1439 and C1445 are cleared when the power switch is turned off.

DTC No. Detection Item INF Code DTC Detection Condition Trouble Area Note
C1439 Steering Angle Sensor Initialization Incomplete 352 After the steering sensor zero point calibration is cleared due to, for example, fluctuations in the power source, the steering sensor zero point calibration cannot be obtained for 0.048 seconds of continuous driving.

  • Steering sensor

  • Yaw rate sensor

  • Skid control ECU assembly

 -
C1445 Vehicle Driven with Steering Angle Sensor not Initialized 353 When no steering sensor zero point is stored and the vehicle is being driven at a speed of 35 km/h (22 mph) or more for 30 seconds or more without the brake pedal having been depressed, the steering sensor zero point cannot be obtained.

  • Steering sensor

  • Yaw rate sensor

  • Skid control ECU 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 source voltage drops when the auxiliary battery is removed. Confirm whether this condition occurred.

PROCEDURE


  1. CHECK DTC


    1. Clear the DTCs.

      Click here


      Chassis > ABS/VSC/TRC > Clear DTCs

    2. Turn the power switch off.

    3. Turn the power switch on (IG) again and check that no CAN communication system DTCs are output.

      Click here

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

      Click here


      Chassis > ABS/VSC/TRC > Trouble Codes
      Result
      Result Proceed to
      DTCs C1439 and/or C1445 are output. A
      CAN communication system DTCs are output. B
      Speed sensor, yaw rate sensor and/or steering sensor DTCs are output. C
      DTCs C1439 and C1445 are not output. D

      Tech Tips


      • When CAN communication system DTCs are output, repair the CAN communication system before repairing each corresponding sensor.

      • If there is a malfunction in a speed sensor or the yaw rate sensor, an abnormal value may be output although the steering sensor is normal.

      • If speed sensor and yaw rate sensor DTCs are output simultaneously, repair these malfunctions and inspect the steering sensor.

      • If DTC C1439 and/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 source voltage drops.


    B

    INSPECT CAN COMMUNICATION SYSTEM Click here

    C

    REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Click here

    D

    USE SIMULATION METHOD TO CHECK Click here

    A

  2. CHECK STEERING 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 steering wheel is centered correctly while driving straight ahead.

      Tech Tips

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

      OK
      The steering wheel is centered correctly.
      Result
      Proceed to
      OK
      NG

    NG

    ADJUST FRONT WHEEL ALIGNMENT OR STEERING POSITION for 2WD: Click here
    ADJUST FRONT WHEEL ALIGNMENT OR STEERING POSITION for AWD: Click here

    OK

  3. RECONFIRM DTC


    1. Clear the DTCs.

      Click here


      Chassis > ABS/VSC/TRC > Clear DTCs

    2. Turn the power switch off.

    3. Turn the power switch on (READY).

    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.

    5. Check if the same DTC is output.

      Click here


      Chassis > ABS/VSC/TRC > Trouble Codes
      Result
      Result Proceed to
      DTCs C1439 and C1445 are not output. A
      yaw rate sensor and/or steering sensor DTCs are output. B

      Tech Tips

      If DTC C1439 and/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 source voltage drops.


    A

    END

    B

    REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Click here