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Home >> Nissan-Datsun >> 2005 >> Sentra SE-R >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Component Testing (Qr25DE) >> 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 

    1. Yes (With CONSULT-II) : GO TO 2.
    2. Yes (Without CONSULT-II) : GO TO  3.
    3. No : GO TO  4.
  2. CHECK OVERALL FUNCTION 

    With CONSULT-II 

    1. Perform "POWER BALANCE" in "ACTIVE TEST" mode with CONSULT-II.
      Fig 1: ACTIVE TEST, POWER BALANCE - CONSULT-II Display Screen
      G02454272Courtesy of NISSAN MOTOR CO., U.S.A.
    2. Make sure that all circuits do not produce a momentary engine speed drop.

    OK or NG 

    1. OK : INSPECTION END 
    2. NG : GO TO  12.
  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 in Fig 2.
      NOTE: The pulse cycle changes depending on rpm at idle.
      Fig 2: Signal Wave Graph
      G02454273Courtesy of NISSAN MOTOR CO., U.S.A.
      Fig 3: Checking Voltage Signal Between ECM Connector Terminals 61, 62, 80, 81 And Ground
      G02454274Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK : INSPECTION END 
    2. NG : GO TO  12.
  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
      1. Voltage: Battery voltage 
      Fig 4: Checking Voltage Between ECM Connector Terminals 119, 120 And Ground
      G02454275Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK : GO TO 5.
    2. NG : Go to "POWER SUPPLY AND GROUND CIRCUIT "
  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 + and ground with CONSULT-II or tester
      1. Voltage: Battery voltage 
      Fig 5: Checking Voltage Between Condenser Connector Terminal + And Ground
      G02454276Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK : GO TO  10.
    2. NG : GO TO 6.
  6. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-III 
    1. Turn ignition switch OFF.
    2. Disconnect ECM relay.
      Fig 6: Locating ECM Relay
      G02454277Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check harness continuity between ECM relay terminal 7 and condenser terminal +. Refer to WIRING DIAGRAM 
      1. Continuity should exist. 
    4. 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 IGNITION COIL POWER SUPPLY CIRCUIT-IV 

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

    1. Voltage: Battery voltage 
    Fig 7: Checking Voltage Between ECM Relay Terminal 6 And Ground
    G02454278Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK : GO TO  9.
    2. NG : GO TO 8.
  8. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E10, F48
    • Fuse and fusible link box connector E22
    • 15A fuse
    • Harness for open or short between ECM relay and battery
      1. : Repair or replace harness or connectors.
  9. CHECK ECM RELAY 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    1. OK : GO TO  16.
    2. 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 - and ground. Refer to WIRING DIAGRAM 
      1. Continuity should exist. 
    4. Also check harness for short to power.

    OK or NG 

    1. OK : GO TO 11.
    2. NG : Repair open circuit or short to power in harness or connector.
  11. CHECK CONDENSER 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    1. OK : GO TO 12.
    2. NG : Replace condenser.
  12. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-V 
    1. Turn ignition switch OFF.
    2. Disconnect ignition coil harness connector.
      Fig 8: Locating Ignition Coil Harness Connector
      G02454279Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Turn ignition switch ON.
    4. Check voltage between ignition coil terminal 3 and ground with CONSULT-II or tester
      1. Voltage: Battery voltage 
      Fig 9: Checking Voltage Between Ignition Coil Connector Terminal 3 And Ground
      G02454280Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK : GO TO 13.
    2. NG : Repair open circuit or short to ground or short to power in harness or connectors.
  13. 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 
      1. Continuity should exist. 
    3. Also check harness for short to power.

    OK or NG 

    1. OK : GO TO 14.
    2. NG : Repair open circuit or short to power in harness or connectors.
  14. 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 
      1. Continuity should exist. 
    3. Also check harness for short to ground and short to power

    OK or NG 

    1. OK : GO TO 15.
    2. NG : Repair open circuit or short to ground or short to power in harness or connectors.
  15. CHECK IGNITION COIL WITH POWER TRANSISTOR 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    1. OK : GO TO 16.
    2. NG : Replace ignition coil with power transistor.
  16. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    1. : INSPECTION END 
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