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Home >> Infiniti >> 2008 >> FX35 AWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System - DTCS P0447 Through P1211 (VQ35DE) >> DTC P0550 PSP Sensor >> Diagnostic Procedure

Diagnostic Procedure

  1. CHECK GROUND CONNECTIONS 
    1. Turn ignition switch OFF.
    2. Loosen and retighten ground screw on the body. Refer to "GROUND INSPECTION ".
    Fig 1: Identifying Body Ground, Steering Column And Blower Motor
    G05216304Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO  2.

    NG: Repair or replace ground connections.

  2. CHECK POWER STEERING PRESSURE (PSP) SENSOR POWER SUPPLY CIRCUIT 
    1. Disconnect power steering pressure (PSP) sensor harness connector.
    2. Turn ignition switch ON.
      Fig 2: Identifying Power Steering Pressure Sensor
      G05216734Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between PSP sensor terminal 1 and ground with CONSULT-III or tester.

      Voltage: Approximately 5V 

    OK or NG 

    OK: GO TO  3.

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

    Fig 3: Checking Voltage Between Power Steering Pressure Sensor Terminal 1 And Ground
    G04875300Courtesy of NISSAN MOTOR CO., U.S.A.
  3. CHECK POWER STEERING PRESSURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check harness continuity between PSP sensor terminal 3 and ECM terminal 67.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

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

    OK or NG 

    OK: GO TO  4.

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

  4. CHECK POWER STEERING PRESSURE SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Check harness continuity between ECM terminal 12 and PSP sensor terminal 2.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

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

    OK or NG 

    OK: GO TO  5.

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

  5. CHECK POWER STEERING PRESSURE SENSOR 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO  6.

    NG: Replace power steering pressure sensor.

  6. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    >> INSPECTION END