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Home >> Nissan-Datsun >> 2004 >> Sentra Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - QG18DE >> DTC P1102: MAF Sensor >> Diagnostic Procedure
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Diagnostic Procedure

  1. RETIGHTEN GROUND SCREWS 
    1. Turn ignition switch OFF.
    2. Loosen and retighten engine ground screws.
      1. GO TO 2.
    Fig 1: Identifying Engine Ground Screws
    G00773766Courtesy of NISSAN MOTOR CO., U.S.A.
  2. CHECK MASS AIR FLOW (MAF) SENSOR POWER SUPPLY CIRCUIT 
    1. Disconnect MAF sensor harness connector.
    2. Turn ignition switch ON.
      Fig 2: Disconnecting MAF Sensor Harness Connector
      G00773767Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between MAF sensor terminals 2, 4 and ground with CONSULT-II or tester.
      Fig 3: MAF Sensor Terminals 2, 4 And Ground Voltage Conditions Chart
      G00773768Courtesy of NISSAN MOTOR CO., U.S.A.
      Fig 4: Checking Voltage Between MAF Sensor Terminals 2, 4 And Ground
      G00773769Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO  6.
    2. NG: GO TO  5.
  3. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness for open or short between ECM relay and mass air flow sensor
    • Harness for open or short between mass air flow sensor and ECM
      1. Repair open circuit or short to ground or short to power in harness or connectors.
  4. CHECK MAF SENSOR GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Disconnect TCM harness connector.
    4. Check harness continuity between MAF sensor terminal 3 and ECM terminal 67, TCM terminal 42.
      1. Continuity should exist. 
    5. Also check harness for short to ground and short to power.

    OK or NG 

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

    Check the following.

    • Harness for open or short between mass air flow sensor and ECM.
    • Harness for open or short between mass air flow sensor and TCM.
      1. Repair open circuit or short to ground or short to power in harness or connectors.
  6. CHECK MAF SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Check harness continuity between MAF sensor terminal 1 and ECM terminal 51.

      Refer to WIRING DIAGRAM .

      1. 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: Repair open circuit or short to ground or short to power in harness or connectors.
  7. CHECK MASS AIR FLOW SENSOR 

    Refer to COMPONENT INSPECTION .

    OK or NG 

    1. OK: GO TO 8.
    2. NG: Replace mass air flow sensor.
  8. CHECK INTERMITTENT INCIDENT 

    Perform TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .

    1. INSPECTION END 
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