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Diagnostic Procedure

  1. INSPECTION START 

    Start engine.

    Is engine running? 

    Yes or No

    Yes: GO TO  8.

    No: GO TO STEP 2.

  2. CHECK ECM POWER SUPPLY CIRCUIT-I 
    1. Turn ignition switch OFF and then ON.
    2. Check voltage between ECM terminal 109 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

    OK or NG

    OK: GO TO  4.

    NG: GO TO STEP 3.

    Fig 1: Check Voltage Between ECM Terminal 109 & Ground
    G02691178Courtesy of NISSAN MOTOR CO., U.S.A.
  3. DETECT MALFUNCTIONING PART 

    Check the following.

    • 10A fuse
    • Harness for open or short between ECM and fuse

      : Repair harness or connectors.

  4. CHECK GROUND CONNECTIONS 
    1. Turn ignition switch OFF.
    2. Loosen and retighten ground three screws on the body.
      Fig 2: Checking Ground Connections
      G02691179Courtesy of NISSAN MOTOR CO., U.S.A.

      Refer to GROUND INSPECTION .

    OK or NG

    OK: GO TO STEP 5.

    NG: Repair or replace ground connections.

  5. CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-I 
    1. Disconnect ECM harness connector.
    2. Check harness continuity between ECM terminals 1,115,116 and body ground. Refer to Wiring Diagram.

      Continuity should exist. 

    3. Also check harness for short to power.

    OK or NG

    OK: GO TO  7.

    NG: GO TO STEP 6.

  6. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors F32, E2
    • Harness for open or short between ECM and body ground

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

  7. CHECK ECM POWER SUPPLY CIRCUIT-II 
    1. Reconnect ECM harness connector.
    2. Turn ignition switch ON.
    3. Check voltage between IPDM E/R terminal 4 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

    OK or NG

    OK: GO to IGNITION SIGNAL .

    NG: GO TO STEP 8.

    Fig 3: Checking Voltage Between IPDM E/R Terminal 4 & Ground
    G02691180Courtesy of NISSAN MOTOR CO., U.S.A.
  8. CHECK ECM POWER SUPPLY CIRCUIT-III 
    1. Turn ignition switch OFF and wait at least 10 seconds.
    2. Turn ignition switch ON and then OFF.
    3. Check voltage between ECM terminals 119, 120 and ground with CONSULT-II or tester.

      Voltage: After turning ignition switch OFF, battery voltage will exist for a few seconds, then drop approximately 0V. 

    OK or NG

    OK: GO TO  16.

    NG (Battery voltage does not exist.): GO TO STEP 9.

    NG (Battery voltage exists for more than a few seconds.): GO TO  16.

    Fig 4: Checking Voltage Between ECM Terminals 119, 120 & Ground
    G02691181Courtesy of NISSAN MOTOR CO., U.S.A.
  9. CHECK ECM POWER SUPPLY CIRCUIT-V 
    1. Turn ignition switch OFF and wait at least 10 seconds.
    2. Check voltage between ECM terminal 111 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

    OK or NG

    OK: GO TO STEP 10.

    NG: GO TO  11.

    Fig 5: Checking Voltage Between ECM Terminal 111 & Ground
    G02691182Courtesy of NISSAN MOTOR CO., U.S.A.
  10. CHECK ECM POWER SUPPLY CIRCUIT-VI 
    1. Disconnect ECM harness connector.
    2. Disconnect IPDM E/R harness connector E119.
    3. Check harness continuity between ECM terminals 119, 120 and IPDM E/R terminal 3. Refer to Wiring Diagram.

      Continuity should exist. 

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

    OK or NG

    OK: GO TO  13.

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

  11. CHECK ECM POWER SUPPLY CIRCUIT-VII 
    1. Disconnect ECM harness connector.
    2. Disconnect IPDM E/R harness connector E119.
    3. Check harness continuity between ECM terminal 111 and IPDM E/R terminal 7.

      Refer to Wiring Diagram.

      Continuity should exist. 

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

    OK or NG

    OK: GO TO STEP 12.

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

  12. CHECK 15A FUSE 
    1. Disconnect 20A fuse from IPDM E/R.
    2. Check 20A fuse.

    OK or NG

    OK: GO TO STEP  16.

    NG: Replace 20A fuse.

  13. CHECK GROUND CONNECTIONS 
    1. Turn ignition switch OFF.
    2. Loosen and retighten ground three screws on the body.
      Fig 6: Checking Ground Connections
      G02691183Courtesy of NISSAN MOTOR CO., U.S.A.

      Refer to GROUND INSPECTION .

    OK or NG

    OK: GO TO STEP 14.

    NG: Repair or replace ground connections.

  14. CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-II 
    1. Disconnect ECM harness connector.
    2. Check harness continuity between ECM terminals 1,115,116 and ground.

      Refer to Wiring Diagram.

      Continuity should exist. 

    3. Also check harness for short to power.

    OK or NG

    OK: GO TO STEP  16.

    NG: GO TO STEP 15.

  15. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors F32, E2
    • Harness for open or short between ECM and ground

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

  16. CHECK INTERMITTENT INCIDENT 

    Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .

    OK or NG

    OK: Replace IPDM E/R.

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

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