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Home >> Nissan-Datsun >> 2004 >> Altima Base, Automatic >> Repair and Diagnosis >> Engine Performance >> Engine Control System - 2.5L >> Refrigerant Pressure Sensor >> Diagnostic Procedure
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Diagnostic Procedure

  1. CHECK REFRIGERANT PRESSURE SENSOR OVERALL FUNCTION 
    1. Start engine and warm it up to normal operating temperature.
    2. Turn A/C switch and blower switch ON.
    3. Check voltage between ECM terminal 70 and ground with CONSULT-II or tester.

      Voltage: 1.0 - 4.0V 

    OK or NG

    1. OK : INSPECTION END 
    2. NG : GO TO 2.
      Fig 1: Checking Voltage Between ECM Terminal 70 & Ground
      G02884992Courtesy of NISSAN MOTOR CO., U.S.A.
  1. CHECK REFRIGERANT PRESSURE SENSOR POWER SUPPLY CIRCUIT 
    1. Turn A/C switch and blower switch OFF.
    2. Stop engine.
    3. Disconnect refrigerant pressure sensor harness connector.
    4. Turn ignition switch ON.
      Fig 2: Disconnecting Refrigerant Pressure Sensor Harness Connector
      G02884993Courtesy of NISSAN MOTOR CO., U.S.A.
    5. Check voltage between refrigerant pressure sensor terminal 1 and ground with CONSULT-II or tester.

      Voltage: Approximately 5V 

    OK or NG

    1. OK : GO TO  3.
    2. NG : GO TO 3.
      Fig 3: Checking Voltage Between Refrigerant Pressure Sensor Terminal 1 & Ground
      G02884994Courtesy of NISSAN MOTOR CO., U.S.A.
  2. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E19, F33
    • Harness for open or short between ECM and refrigerant pressure sensor
    1. : Repair harness or connectors.
  3. CHECK REFRIGERANT PRESSURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check harness continuity between refrigerant pressure 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

    1. OK : GO TO  5.
    2. NG : GO TO 5.
  4. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E19, F33
    • Harness for open or short between ECM and refrigerant pressure sensor
    1. : Repair open circuit or short to ground or short to power in harness or connectors.
  5. CHECK REFRIGERANT PRESSURE SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Check harness continuity between ECM terminal 70 and refrigerant pressure 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

    1. OK : GO TO  7.
    2. NG : GO TO 7.
  6. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E19, F33
    • Harness for open or short between ECM and refrigerant pressure sensor
    1. : Repair open circuit or short to ground or short to power in harness or connectors.
  7. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    OK or NG

    1. OK : Replace refrigerant pressure sensor.
    2. NG : Repair or replace.
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