LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Nissan-Datsun >> 2008 >> Quest Base >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System - DTCS P0444 Through P1168 >> DTC P0550 PSP Sensor >> Diagnostic Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnostic 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 Ground Screws On Body
      G04905661Courtesy 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 power steering pressure (PSP) sensor harness connector.
    2. Turn ignition switch ON.
      Fig 2: Identifying Power Steering Pressure (PSP) Sensor Harness Connector
      G04905658Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between PSP sensor terminal 3 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 PSP Sensor Terminal 3 And Ground
    G04894984Courtesy of NISSAN MOTOR CO., U.S.A.
  3. 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 1 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 PSP 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 PSP SENSOR 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO 6.

    NG: Replace PSP sensor.

  6. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    : INSPECTION END