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Home >> Lexus >> 2008 >> IS F >> Repair and Diagnosis >> Steering >> Power Steering >> Power Assist Systems >> Power Steering System >> DTC C1528: Motor Rotation Angle Sensor Malfunction >> Inspection Procedure
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Inspection Procedure

  1. CHECK POWER STEERING EARTH WIRE (POWER STEERING GEAR ASSEMBLY - BODY GROUND) 
    1. Check the installation condition of the power steering earth wire connected to the power steering gear assembly.

      OK: The power steering earth wire is securely installed to the power steering gear assembly and body ground. 

      NG: REINSTALL POWER STEERING EARTH WIRE 

      OK: Go to next Step 

  2. CHECK HARNESS AND CONNECTOR (POWER STEERING ECU ASSEMBLY - MOTOR ROTATION ANGLE SENSOR) 
    1. Disconnect the C2 connector from the motor rotation angle sensor (power steering gear assembly)
    2. Disconnect the C4 connector from the power steering ECU assembly
    3. Measure the resistance according to the value (s) in the table below

      Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

    Tester Connection Condition Specified Condition
    C2-1 (RZSN) - C4-7 (RZSN) Always Below 1 Ω
    C2-2 (RZG) - C4-1 (RZG) Always Below 1 Ω
    C2-3 (RZV) - C4-3 (RZV) Always Below 1 Ω
    C2-4 (RZCS) - C4-8 (RZCS) Always Below 1 Ω
    C2-1 (RZSN) - Body ground Always 10 kΩ or higher
    C2-2 (RZG) - Body ground Always 10 kΩ or higher
    C2-3 (RZV) - Body ground Always 10 kΩ or higher
    C2-4 (RZCS) - Body ground Always 10 kΩ or higher
    Fig 1: Identifying C2 And C4 Connector Terminals
    G05752938Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next Step 

  3. INSPECT POWER STEERING GEAR ASSEMBLY (MOTOR ROTATION ANGLE SENSOR) 
    1. Measure the resistance according to the value (s) in the table below.

      Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

    Tester Connection Condition Specified Condition
    C2-1 (RZSN) - C2-2 (RZG) Always 50 to 140 Ω
    C2-3 (RZV) - C2-2 (RZG) Always 50 to 140 Ω
    C2-4 (RZCS) - C2-2 (RZG) Always 15 to 45 Ω
    NOTE: If replacing the power steering gear assembly, clear the rotation angle sensor calibration value, initialize the rotation angle sensor value, and calibrate the torque sensor zero point (See CALIBRATION ).
    Fig 2: Identifying Motor Rotation Angle Sensor Connector Terminals
    G05752939Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE POWER STEERING GEAR ASSEMBLY  (See REMOVAL )

    OK: Go to next Step 

  4. REPLACE POWER STEERING ECU ASSEMBLY 
    1. Replace the power steering ECU assembly (See POWER STEERING ECU ).
  5. INITIALIZE ROTATION ANGLE SENSOR AND CALIBRATE TORQUE SENSOR ZERO POINT 
    1. Initialize the rotation angle sensor value and calibrate the torque sensor zero point (See CALIBRATION ).
  6. RECONFIRM DTC 
    1. Check for DTCs (See DTC CHECK/CLEAR ).

      Result 

    RESULT CHART

    Result Proceed to
    DTC is not output A
    DTC C1528 is output B
    NOTE: If replacing the power steering gear assembly, clear the rotation angle sensor calibration value, initialize the rotation angle sensor value, and calibrate the torque sensor zero point (See CALIBRATION ).

    B: REPLACE POWER STEERING GEAR ASSEMBLY  (See REMOVAL )

    A: END 

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