Diagnosis Procedure

Regarding Wiring Diagram information, refer to "WIRING DIAGRAM-ENGINE CONTROL SYSTEM- ".

1. INSPECTION START

   Confirm the detected malfunction (A or B). Refer to "DTC LOGIC ".

   Which malfunction is detected? 

   A: GO TO  3.

   B: GO TO 2.

2. CHECK INTAKE SYSTEM

   Check the following for connection.

   • Air duct
   • Vacuum hoses
   • Intake air passage between air duct and intake manifold

     Is the inspection result normal? 

     YES: GO TO 3.

     NO: Reconnect the parts.

3. CHECK GROUND CONNECTION
   1. Turn ignition switch OFF.
   2. Check ground connection E9. Refer to Ground Inspection in "CIRCUIT INSPECTION ".

      Is the inspection result normal? 

      YES: GO TO 4.

      NO: Repair or replace ground connection.

4. CHECK MAF SENSOR POWER SUPPLY CIRCUIT
   1. Disconnect mass air flow (MAF) sensor harness connector.
   2. Turn ignition switch ON.
   3. Check the voltage between MAF sensor harness connector and ground.

      MAF sensor		Ground	Voltage
      Connector	Terminal
      F31	2	Ground	Battery voltage

      Is the inspection result normal? 

      YES: GO TO  6.

      NO: GO TO 5.

      Fig 1: Checking Voltage Between MAF Sensor Terminal 2 And Ground

      Courtesy of NISSAN NORTH AMERICA, INC.
5. DETECT MALFUNCTIONING PART

   Check the following.

   • Harness connectors E11, F2
   • Junction block connectors E44, E45
   • Harness for open or short between mass air flow sensor and ECM
   • Harness for open or short between mass air flow sensor and IPDM E/R

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

6. CHECK MAF SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
   1. Turn ignition switch OFF.
   2. Disconnect ECM harness connector.
   3. Check the continuity between MAF sensor harness connector and ECM harness connector.

      MAF sensor		ECM		Continuity
      Connector	Terminal	Connector	Terminal
      F31	3	F13	56	Existed

   4. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO 7.

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

7. CHECK MAF SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
   1. Check the continuity between MAF sensor harness connector and ECM harness connector.

      MAF sensor		ECM		Continuity
      Connector	Terminal	Connector	Terminal
      F31	4	F13	58	Existed

   2. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO 8.

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

8. CHECK INTAKE AIR TEMPERATURE SENSOR

   Refer to "COMPONENT INSPECTION ".

   Is the inspection result normal? 

   YES: GO TO 9.

   NO: Replace mass air flow sensor (with intake air temperature sensor). Refer to AIR CLEANER AND AIR DUCT .

9. CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

   Refer to "COMPONENT INSPECTION ".

   Is the inspection result normal? 

   YES: GO TO 10.

   NO: Replace EVAP control system pressure sensor. Refer to "REMOVAL AND INSTALLATION ".

10. CHECK MASS AIR FLOW SENSOR

    Refer to "COMPONENT INSPECTION ".

    Is the inspection result normal? 

    YES: GO TO 11.

    NO: Replace mass air flow sensor. Refer to "REMOVAL AND INSTALLATION ".

11. CHECK INTERMITTENT INCIDENT

    Refer to "INTERMITTENT INCIDENT ".

    : INSPECTION END