LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Infiniti >> 2008 >> EX35 Base, AWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System - DTCS U1000 To P0153 >> P0133, P0153 A/F Sensor 1 >> Diagnosis Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnosis Procedure

  1. CHECK GROUND CONNECTION
    1. Turn ignition switch OFF.
    2. Check ground connection M95. Refer to Ground Inspection in "CIRCUIT INSPECTION ".

    Is the inspection result normal? 

    YES: GO TO 2.

    NO: Repair or replace ground connection.

  2. RETIGHTEN A/F SENSOR 1

    Loosen and retighten the A/F sensor 1. Refer to "REMOVAL AND INSTALLATION ".

    GO TO 3.

  3. CHECK EXHAUST GAS LEAK
    1. Start engine and run it at idle.
    2. Listen for an exhaust gas leak before three way catalyst 1.
      Fig 1: Checking Exhaust Gas Leak
      G04875054Courtesy of NISSAN MOTOR CO., U.S.A.

    Is exhaust gas leak detected? 

    YES: Repair or replace malfunctioning part.

    NO: GO TO 4.

  4. CHECK FOR INTAKE AIR LEAK

    Listen for an intake air leak after the mass air flow sensor.

    Is intake air leak detected? 

    YES: Repair or replace malfunctioning part.

    NO: GO TO 5.

  5. CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE
    1. Clear the mixture ratio self-learning value. Refer to "MIXTURE RATIO SELF-LEARNING VALUE CLEAR : SPECIAL REPAIR REQUIREMENT ".
    2. Run engine for at least 10 minutes at idle speed.

    Is the 1st trip DTC P0171, P172, P0174 or P0175 detected? Is it difficult to start engine? 

    YES: Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. Refer to "DTC LOGIC " or "DTC LOGIC ".

    NO: GO TO 6.

  6. CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT
    1. Disconnect A/F sensor 1 harness connector.
    2. Turn ignition switch ON.
    3. Check the voltage between A/F sensor 1 harness connector and ground.
      VOLTAGE SPECIFICATIONS

      DTC A/F sensor 1 Ground Voltage
      Bank Connector Terminal
      P0133 1 F3 4 Ground Battery voltage
      P0153 2 F20 4

    Is the inspection result normal? 

    YES: GO TO  8.

    NO: GO TO 7.

  7. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E3, F1
    • IPDM E/R harness connector E7
    • 15A fuse (No. 46)
    • Harness for open or short between A/F sensor 1 and fuse

      Repair or replace harness or connectors.

  8. CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check the continuity between A/F sensor 1 harness connector and ECM harness connector.
      CONTINUITY SPECIFICATIONS

      DTC A/F sensor 1 ECM Continuity
      Bank Connector Terminal Connector Terminal
      P0133 1 F3 1 F102 57 Existed
      2 61
      P0153 2 F20 1 65
      2 66
    4. Check the continuity between A/F sensor 1 harness connector or ECM harness connector and ground.
      CONTINUITY SPECIFICATIONS

      DTC A/F sensor 1 ECM Ground Continuity
      Bank Connector Terminal Connector Terminal
      P0133 1 F3 1 F102 57 Ground Not existed
      2 61
      P0153 2 F20 1 65
      2 66
    5. Also check harness for short to power.

    Is the inspection result normal? 

    YES: GO TO 9.

    NO: Repair open circuit or short to ground or short to power in harness or connectors.

  9. CHECK AIR FUEL RATIO (A/F) SENSOR 1 HEATER

    Refer to "COMPONENT INSPECTION ".

    Is the inspection result normal? 

    YES: GO TO 10.

    NO: GO TO  13.

  10. CHECK MASS AIR FLOW SENSOR

    Check both mass air flow sensor (bank 1 and bank 2).

    Refer to "COMPONENT INSPECTION ".

    Is the inspection result normal? 

    YES: GO TO 11.

    NO: Replace malfunctioning mass air flow sensor.

  11. CHECK PCV VALVE

    Refer to "COMPONENT INSPECTION ".

    Is the inspection result normal? 

    YES: GO TO 12.

    NO: Repair or replace PCV valve.

  12. CHECK INTERMITTENT INCIDENT

    Perform "INTERMITTENT INCIDENT ".

    Is the inspection result normal? 

    YES: GO TO 13.

    NO: Repair or replace malfunctioning part.

  13. REPLACE AIR FUEL RATIO (A/F) SENSOR 1

    Replace malfunctioning air fuel ratio (A/F) sensor 1.

    CAUTION:
    • Discard any A/F sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a hard surface such as a concrete floor; use a new one.
    • Before installing new A/F sensor, clean exhaust system threads using Oxygen Sensor Thread Cleaner [commercial service tool (J-43897-18 or J-43897-12)] and approved anti-seize lubricant (commercial service tool).

    INSPECTION END

scientia non olet · About LEMON Manuals