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Home >> Infiniti >> 2010 >> M45 Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTCS P0460 To P1421 >> DTC P0550 PSP Sensor >> Diagnosis Procedure
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Diagnosis Procedure

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

    Refer to "GROUND INSPECTION ".

    Fig 1: Identifying Body Ground (M70 And M16)
    G06303284Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO 2.

    NG: Repair or replace ground connections.

  2. CHECK PSP SENSOR POWER SUPPLY CIRCUIT
    1. Disconnect PSP sensor (1) harness connector.
      • Illustration shows the view from under the vehicle.
    2. Turn ignition switch ON.
      Fig 2: Identifying Power Steering Pressure (PSP) Sensor
      G05210858Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between PSP sensor terminal 1 and ground with CONSULT-III or tester.

    Voltage: Approximately 5 V 

    OK or NG 

    OK: GO TO  4.

    NG: GO TO 3.

    Fig 3: Checking Voltage Between PSP Sensor Terminal 1 And Ground
    G04875300Courtesy of NISSAN MOTOR CO., U.S.A.
  3. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E206, E72
    • Harness connectors E11, F2
    • Harness for open or short between power steering pressure sensor and ECM

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

  4. CHECK PSP 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 SYSTEM WIRING DIAGRAMS article.

      Continuity should exist  .

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

    OK or NG 

    OK: GO TO  6.

    NG: GO TO 5.

  5. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E206, E72
    • Harness connectors E11, F2
    • Harness for open or short between power steering pressure sensor and ECM

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

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

      Refer to SYSTEM WIRING DIAGRAMS article.

      Continuity should exist  .

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

    OK or NG 

    OK: GO TO  8.

    NG: GO TO 7.

  7. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E206, E72
    • Harness connectors E11, F2
    • Harness for open or short between power steering pressure sensor and ECM

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

  8. CHECK PSP SENSOR

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO 9.

    NG: Replace PSP sensor.

  9. CHECK INTERMITTENT INCIDENT

    Refer to "DIAGNOSIS PROCEDURE ".

    INSPECTION END 

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