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Home >> Nissan-Datsun >> 2006 >> Sentra Base, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Component Testing (QG18DE) >> Ignition Signal >> Diagnostic Procedure
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Diagnostic Procedure

  1. CHECK ENGINE START 

    Turn ignition switch OFF, and restart engine.

    Is engine running? 

    Yes or No 

    Yes (With CONSULT-II): GO TO  2.

    Yes (Without CONSULT-II): GO TO  3.

    No: GO TO  4.

  2. CHECK OVERALL FUNCTION 

    With CONSULT-II 

    1. Perform "POWER BALANCE" in "ACTIVE TEST" mode with CONSULT-II.
    2. Make sure that each circuit produces a momentary engine " speed drop.

    OK or NG 

    OK: INSPECTION END 

    NG: GO TO  10.

    Fig 1: Consult-II ACTIVE TEST Display Screen
    G04080452Courtesy of NISSAN MOTOR CO., U.S.A.
  3. CHECK OVERALL FUNCTION 

    Without CONSULT-II 

    1. Let engine idle.
    2. Read the voltage signal between ECM terminals 61, 62, 80, 81 and ground with an oscilloscope.
    3. Verify that the oscilloscope screen shows the signal wave as shown below.
      NOTE: The pulse cycle changes depending on rpm at idle.
      Fig 2: Checking Voltage Signal Between ECM Terminals 61, 62, 80, 81 And Ground
      G04191494Courtesy of NISSAN MOTOR CO., U.S.A.
      Fig 3: View OF Voltage Waveform Pattern
      G04147122Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: INSPECTION END 

    NG: GO TO  10.

  4. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-I 
    1. Turn ignition switch ON.
    2. Check voltage between ECM terminals 119, 120 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

    OK or NG 

    OK: GO TO  5.

    NG: Go to "POWER SUPPLY AND GROUND CIRCUIT ".

    Fig 4: Checking Voltage Between ECM Terminals 119, 120 And Ground
    G04191495Courtesy of NISSAN MOTOR CO., U.S.A.
  5. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-II 
    1. Turn ignition switch OFF.
    2. Disconnect condenser harness connector.
    3. Turn ignition switch ON.
    4. Check voltage between condenser terminal 1 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

    OK or NG 

    OK: GO TO  10.

    NG: GO TO  6.

    Fig 5: Checking Voltage Between Terminal 1 And Ground
    G04075312Courtesy of NISSAN MOTOR CO., U.S.A.
  6. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-III 
    1. Turn ignition switch OFF.
    2. Disconnect ECM relay.
    3. Check harness continuity between ECM relay terminal 7 and condenser terminal 1.

      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  7.

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

    Fig 6: Disconnecting ECM Relay
    G04191497Courtesy of NISSAN MOTOR CO., U.S.A.
  7. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-IV 

    Check voltage between ECM relay terminal 6 and ground with CONSULT-II or tester.

    Voltage: Battery voltage 

    OK or NG 

    OK: GO TO  9.

    NG: GO TO  8.

    Fig 7: Checking Voltage Between ECM Relay Terminal 6 And Ground
    G04191498Courtesy of NISSAN MOTOR CO., U.S.A.
  8. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E10, F48
    • 15A fuse
    • Harness for open or short between ECM relay and battery

    : Repair or replace harness or connectors.

  9. CHECK ECM RELAY 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO  17.

    NG: Replace ECM relay.

  10. CHECK CONDENSER GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect condenser harness connector.
    3. Check harness continuity between condenser terminal 2 and ground.

      Refer to WIRING DIAGRAM .

      Continuity should exist  .

    4. Also check harness for short to power.

    OK or NG 

    OK: GO TO  11.

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

  11. CHECK CONDENSER 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO  12.

    NG: Replace condenser.

  12. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-V 
    1. Turn ignition switch OFF.
    2. Reconnect all harness connectors disconnected.
    3. Disconnect ignition coil harness connector.
    4. Turn ignition switch ON.
      Fig 8: Disconnecting Ignition Coil Harness Connector
      G04191499Courtesy of NISSAN MOTOR CO., U.S.A.
    5. Check voltage between ignition coil terminal 3 and ground with CONSULT-II or tester.

    Voltage: Battery voltage 

    OK or NG 

    OK: GO TO  14.

    NG: GO TO  13.

    Fig 9: Checking Voltage Between Connector Terminal 3 And Ground
    G04075010Courtesy of NISSAN MOTOR CO., U.S.A.
  13. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness for open or short between ignition coil and ECM relay

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

  14. CHECK IGNITION COIL GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Check harness continuity between ignition coil terminal 2 and ground.

      Refer to WIRING DIAGRAM .

      Continuity should exist  .

    3. Also check harness for short to power.

    OK or NG 

    OK: GO TO  15.

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

  15. CHECK IGNITION COIL OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Disconnect ECM harness connector.
    2. Check harness continuity between ECM terminals 61, 62, 80, 81 and ignition coil terminal 1.

      Refer to WIRING DIAGRAM .

      Continuity should exist  .

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

    OK or NG 

    OK: GO TO  16.

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

  16. CHECK IGNITION COIL WITH POWER TRANSISTOR 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO  17.

    NG: Replace ignition coil with power transistor.

  17. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    : INSPECTION END 

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