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Home >> Infiniti >> 2021 >> Q50 Pure, AWD >> Repair and Diagnosis (Single Page) >> Steering >> Steering Control Systems >> Steering Control System (Diagnostics) >> Symptom Diagnosis >> Unbalance Steering Wheel Turning Force (Torque Variation) >> Diagnosis Procedure >> Without Direct Adaptive Steering System
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Without Direct Adaptive Steering System

  1. PERFORM SELF-DIAGNOSIS 

    SYMBOL With CONSULT

    1. Turn the ignition switch OFF to ON.
    2. Perform "EPS/DAST 3" self-diagnosis.

    Is a malfunctioning system displayed?

    YES

    Check the DTC. Refer to DTC Index .

    NO

    GO TO 2.

  2. CHECK THE ILLUMINATION OF THE POWER STEERING WARNING LAMP 

    Check that the power steering warning lamp turns ON when ignition switch turns ON. Then, power steering warning lamp turns OFF after the engine is started.

    Is the inspection result normal?

    YES

    GO TO 3.

    NO

    Perform trouble diagnosis of power steering warning lamp. Refer to Diagnosis Procedure .

  3. CHECK STEERING COLUMN AND STEERING GEAR 

    Check the steering column assembly and steering gear assembly.

    Is the inspection result normal?

    YES

    GO TO 4.

    NO

    Repair or replace error-detected parts.

  4. CHECK THE POWER STEERING CONTROL MODULE SIGNAL (1) 

    SYMBOL With CONSULT

    1. Start the engine.
      CAUTION: Never drive the vehicle.
    2. Turn steering wheel from full left stop to full right stop.
    3. Select "Assist level" in "DATA MONITOR" in "EPS/DAST 3".

    Is the display value "100%"?

    YES

    GO TO 7.

    NO

    GO TO 5.

  5. CHECK THE POWER STEERING CONTROL MODULE SIGNAL (2) 

    SYMBOL With CONSULT

    Select "BATTERY VOLT" in "DATA MONITOR" in "EPS/DAST 3".

    Is the display value "10.5 V" or more?

    YES

    GO TO 6.

    NO

    Perform trouble diagnosis of power steering control module power supply and ground. Refer to DTC Diagnosis Procedure .

  6. CHECK POWER STEERING CONTROL MODULE SIGNAL (3) 

    SYMBOL With CONSULT

    1. Select "Assist level" in "DATA MONITOR" in "EPS/DAST 3".
    2. Stop the EPS system until the item in "DATA MONITOR" becomes "100%".
      NOTE: While stopping the EPS system, do not turn steering wheel.
    3. Check that the symptom continues.

    Dose the symptom continue?

    YES

    GO TO 7.

    NO

    The assist torque decreases because of protection function. This is not malfunction. INSPECTION END

  7. CHECK POWER STEERING CONTROL MODULE SIGNAL (4) 

    SYMBOL With CONSULT

    1. Start the engine.
      CAUTION: Never drive the vehicle.
    2. Turn steering wheel from full left stop to full right stop.
    3. Select "STEERING TORQUE" in "DATA MONITOR" in "EPS/DAST 3".
    4. Perform the torque sensor inspection.

      Monitor item

      Condition

      Display value

      STEERING TORQUE

      Steering wheel: Not steering (There is no steering force)

      Approx. 0 Nm

      Steering wheel: Right turn

      Positive value (Nm)

      Steering wheel: Left turn

      Negative value (Nm)

    Is the inspection result normal?

    YES

    GO TO 9.

    NO

    GO TO 8.

  8. CHECK EPS MOTOR 

    Perform the trouble diagnosis of EPS motor. Refer to DTC Diagnosis Procedure .

    Is the inspection result normal?

    YES

    GO TO 9.

    NO

    Repair or replace the specific malfunctioning part.

  9. CHECK THE STEERING FORCE 

    Check the steering wheel turning force.

    Is the check result normal?

    YES

    INSPECTION END

    NO

    It is possible that there is a mechanical malfunction. Check the steering system. Refer to STEERING GEAR AND LINKAGE : Inspection .

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