2009 Infiniti M35 BaseFACTORY OEM SERVICE PROCEDURE

Diagnosis Procedure

  1. CHECK GROUND CONNECTION
    1. Turn A/C switch and blower fan switch OFF.
    2. Turn ignition switch OFF.
    3. Check ground connections M16, M70. Refer to "GROUND INSPECTION ".

      Is the inspection result normal? 

      YES: GO TO 2.

      NO: Repair or replace ground connections.

  2. CHECK REFRIGERANT PRESSURE SENSOR POWER SUPPLY CIRCUIT
    1. Disconnect refrigerant pressure sensor harness connector.
    2. Turn ignition switch ON.
    3. Check the voltage between refrigerant pressure sensor harness connector and ground.
      CONNECTOR TERMINAL VOLTAGE CHART

      Refrigerant pressure sensor Ground Voltage (V)
      Connector Terminal
      E66 1 Ground Approx. 5
      Fig 1: Checking Voltage Between Refrigerant Pressure Sensor Terminal 1 And Ground
      G05867569Courtesy of NISSAN MOTOR CO., U.S.A.

      Is the inspection result normal? 

      YES: GO TO  4.

      NO: GO TO 3.

  3. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E108, M15
    • Harness for open or short between ECM and refrigerant pressure sensor

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

  4. CHECK REFRIGERANT PRESSURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check the continuity between refrigerant pressure sensor harness connector and ECM harness connector.
      CONNECTOR TERMINAL CONTINUITY CHART

      Refrigerant pressure sensor ECM Continuity
      Connector Terminal Connector Terminal
      E66 3 M9 116 Existed
    4. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO  6.

      NO: GO TO 5.

  5. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E108, M15
    • Harness for open or short between ECM and refrigerant pressure sensor

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

  6. CHECK REFRIGERANT PRESSURE SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
    1. Check the continuity between refrigerant pressure sensor harness connector and ECM harness connector.
      CONNECTOR TERMINAL CONTINUITY CHART

      Refrigerant pressure sensor ECM Continuity
      Connector Terminal Connector Terminal
      E66 2 M9 105 Existed
    2. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO  8.

      NO: GO TO 7.

  7. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E108, M15
    • Harness for open or short between ECM and refrigerant pressure sensor

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

  8. CHECK INTERMITTENT INCIDENT

    Refer to "DESCRIPTION ".

    Is the inspection result normal? 

    YES: Replace refrigerant pressure sensor.

    NO: Repair or replace malfunctioning part.

Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.