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Home >> Infiniti >> 2018 >> QX30 Essential, AWD >> Repair and Diagnosis (Single Page) >> Steering >> Steering Control Systems >> Steering Control System (DTC/Circuit Diagnosis) >> DTC/Circuit Diagnosis >> DTC P1644: Control Unit >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK THE REPLACEMENT HISTORY OF STEERING COMPONENT PARTS 

    Check the replacement history of steering component parts.

    Was the steering component parts replaced?

    YES

    GO TO 2.

    NO

    GO TO 3.

  2. CHECK THE SPECIFICATION OF STEERING COMPONENT PARTS 

    Check the specification of steering component parts.

    Is the specification of steering component parts correct?

    YES

    GO TO 4.

    NO

    Replace steering gear assembly. Refer to Removal and Installation .

  3. PERFORM THE SCN CODING OF ELECTRONIC IGNITION SWITCH CONTROL UNIT 

    Perform the SCN coding of electronic ignition switch control unit.

    GO TO 4.

  4. PERFORM THE RESET OF CODING OF EPS CONTROL UNIT 

    Perform the reset of coding of EPS control unit. Refer to Description .

    INSPECTION END