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DTC    C1439/66    Steering Angle Sensor Initialization Incomplete

DTC    C1445/66    Vehicle Driven with Steering Angle Sensor not Initialized

for Preparation Click here


DESCRIPTION

The skid control ECU acquires the steering angle 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 C1439/66 and C1445/66 will be cleared when the power switch is turned off.

DTC Code
INF Code
DTC Detection Condition
Trouble Area
C1439/66
752
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.
  1. Steering angle sensor
  2. Yaw rate and acceleration sensor
  3. Brake booster with master cylinder (Skid control ECU)
C1445/66
753
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 60 seconds or more without the brake pedal being depressed.
  1. Steering angle sensor
  2. Yaw rate and acceleration sensor
  3. Brake booster with master cylinder (Skid control ECU)

INSPECTION PROCEDURE

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

HINT:
  1. When DTC U0073/94, U0123/62, U0124/95 and/or U0126/63 is output together with DTC C1439/66 and/or C1445/66, inspect and repair the trouble areas indicated by DTC U0073/94, U0123/62, U0124/95 and/or U0126/63 first (Click here).
  2. When the speed sensor or the yaw rate and acceleration sensor has trouble, DTCs for the steering angle sensor may be output even when the steering angle sensor is normal. When DTCs for the speed sensor or yaw rate and acceleration sensor are output together with other DTCs for the steering angle sensor, inspect and repair the speed sensor and yaw rate and acceleration sensor first, and then inspect and repair the steering angle sensor.

1.CHECK DTC

  1. Clear the DTCs (Click here).

  1. Turn the power switch off.

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

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

    Result:

    Result
    		Proceed to
    DTCs (C1439/66 and/or C1445/66) are output
    		A
    CAN communication system DTC is output
    		B
    Speed sensor, yaw rate and acceleration sensor and/or steering angle sensor DTC is output
    		C
    DTCs (C1439/66 and C1445/66) are not output
    		D

    HINT:
    1. When DTCs indicating CAN communication system malfunctions are output, repair the CAN communication system before repairing each corresponding sensor.
    2. If there is a malfunction in the speed sensor or the yaw rate and acceleration sensor, an abnormal value may be output although the steering angle sensor is normal.
    3. If the speed sensor and the yaw rate and acceleration sensor DTCs are output simultaneously, repair the sensors and inspect the steering angle sensor.
    4. If the same DTC C1439/66 and/or C1445/66 is not output again, the DTC may have been stored due to a temporary loss of the steering angle zero 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
CHECK FOR INTERMITTENT PROBLEMS (Click here)
A


2.CHECK 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.

  1. Check that the steering wheel is centered correctly while driving straight ahead.

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

OK:
The steering wheel is centered correctly.



NG
ADJUST FRONT WHEEL ALIGNMENT OR STEERING POSITION (Click here)
OK


3.RECONFIRM DTC

  1. Turn the power switch off.

  1. Clear the DTCs (Click here).

  1. Turn the power switch on (READY).

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

  1. Check if the same DTC is recorded (Click here).

    Result:

    Result
    		Proceed to
    DTCs (C1439/66 and C1445/66) are not output
    		A
    Yaw rate and acceleration sensor and/or steering angle sensor DTC is output
    		B

    HINT:
    If the same DTC C1439/66 and/or C1445/66 is not output again, the DTC may have been stored due to a temporary loss of the steering angle zero calibration, such as when the power source voltage drops.



B
REPAIR CIRCUITS INDICATED BY OUTPUT DTCS (Click here)
A

END