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Home >> Infiniti >> 2008 >> QX56 AWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System - DTCS P0327 To P1145 >> DTC P1140, P1145: IVT Control Position Sensor >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK GROUND CONNECTIONS
    1. Turn ignition switch OFF.
    2. Loosen and retighten three ground screws on the body.

      Refer to "GROUND INSPECTION ".

      Fig 1: Identifying Body Ground Screw
      G05739592Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO 2.

    NG: Repair or replace ground connections.

  2. CHECK INTAKE VALVE TIMING CONTROL POSITION SENSOR POWER SUPPLY CIRCUIT
    1. Disconnect intake valve timing control position sensor harness connector.
      Fig 2: Identifying Intake Valve Timing Control Position Sensor Harness Connector
      G05739593Courtesy of NISSAN MOTOR CO., U.S.A.
    2. Turn ignition switch ON.
    3. Check voltage between intake valve timing control position sensor terminal 3 and ground with CONSULT-III or tester.

      Voltage: Battery voltage 

    OK or NG 

    OK: GO TO  4.

    NG: GO TO 3.

    Fig 3: Checking Voltage Between Intake Valve Timing Control Position Sensor Terminal 3 And Ground
    G05739594Courtesy of NISSAN MOTOR CO., U.S.A.
  3. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E2, F32
    • Harness for open or short between intake valve timing control position sensor and IPDM E/R
    • Harness for open or short between intake valve timing control position sensor and ECM

      Repair open circuit or short to ground or short to power in harness or connectors.

  4. CHECK INTAKE VALVE TIMING CONTROL POSITION SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
    1. Turn ignition switch OFF.
    2. Check harness continuity between intake valve timing control position sensor terminal 1 and ground.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

    3. Also check harness for short to power.

    OK or NG 

    OK: GO TO  6.

    NG: GO TO 5.

  5. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E2, F32
    • Harness for open or short between intake valve timing control position sensor and ground

      Repair open circuit or short to power in harness or connectors.

  6. CHECK INTAKE VALVE TIMING CONTROL POSITION SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
    1. Disconnect ECM harness connector.
    2. Check harness continuity between the following;

      ECM terminal 72 and intake valve timing control position sensor (Bank 1) terminal 2 or

      ECM terminal 53 and intake valve timing control position sensor (Bank 2) terminal 2.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

    3. Also check harness for short to ground and short to power.

    OK or NG 

    OK: GO TO 7.

    NG: Repair open circuit or short to ground or short to power in harness or connectors.

  7. CHECK INTAKE VALVE TIMING CONTROL POSITION SENSOR

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO 8.

    NG: Replace malfunctioning intake valve timing control position sensor. Refer to INTAKE VALVE TIMING CONTROL POSITION SENSOR (LH) .

  8. CHECK CRANKSHAFT POSITION SENSOR (POS)

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO 9.

    NG: Replace crankshaft position sensor (POS).

  9. CHECK CAMSHAFT POSITION SENSOR (PHASE)

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO 10.

    NG: Replace camshaft position sensor (PHASE). Refer to INTAKE VALVE TIMING CONTROL POSITION SENSOR (LH) .

  10. CHECK CAMSHAFT SPROCKET

    Check accumulation of debris to the signal pick-up portion of the camshaft sprocket. Refer to "INSPECTION AFTER INSTALLATION ".

    OK or NG 

    OK: GO TO 11.

    NG: Remove debris and clean the signal pick-up cutout of camshaft sprocket.

  11. CHECK INTERMITTENT INCIDENT

    Refer to "HOW TO CHECK TERMINAL " and "INTERMITTENT INCIDENT ".

    INSPECTION END