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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. SEARCH FOR MALFUNCTIONING CIRCUIT 

    With CONSULT-II 

    1. Perform "POWER BALANCE" in "ACTIVE TEST" mode with CONSULT-II.
    2. Search for circuit which does not produce a momentary engine speed drop.
      Fig 1: Searching For Malfunctioning Circuit With CONSULT-II
      G00781318Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK INSPECTION END 
    2. NG GO TO  13 .
  3. CHECK OVERALL FUNCTION 

    Without CONSULT-II 

    1. Let engine idle.
    2. Read the voltage signal between ECM terminals 60, 61, 62, 79, 80, 81 and ground with oscilloscope.
    3. Verify that the oscilloscope screen shows the signal wave as shown below.
      Fig 2: Checking Overall Function Without CONSULT-II
      G00781319Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK INSPECTION END 
    2. NG GO TO  14 .
  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.
      Fig 3: Checking Voltage Between ECM Terminals 119, 120 And Ground
      G00781320Courtesy of NISSAN MOTOR CO., U.S.A.

    Voltage: Battery voltage 

    OK or NG 

    1. OK GO TO 5.
    2. NG Go to TROUBLE DIAGNOSIS FOR POWER SUPPLY  .
  5. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-II 
    1. Turn ignition switch OFF.
    2. Disconnect condenser harness connector.
      Fig 4: Locating Condenser Harness Connector
      G00781321Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Turn ignition switch ON.
    4. Check voltage between condenser terminal 1 and ground with CONSULT-II or tester.
      Fig 5: Checking Voltage Between Condenser Terminal 1 And Ground
      G00781322Courtesy of NISSAN MOTOR CO., U.S.A.

      Voltage: Battery voltage 

    OK or NG 

    1. OK GO TO  11 .
    2. NG GO TO 6.
  6. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-III 
    1. Turn ignition switch OFF.
    2. Disconnect ECM relay.
      Fig 6: Identifying ECM Relay
      G00781323Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check harness continuity between ECM relay terminal 3 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 

    1. OK GO TO  8 .
    2. NG GO TO 7.
  7. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E1, M1
    • Harness connectors M33, F22
    • Harness for open or short between ECM relay and condenser
    1. Repair open circuit or short to ground or short to power in harness or connectors.
  8. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-IV 

    Check voltage between ECM relay terminal 5 and ground with CONSULT-II or tester.

    Fig 7: Checking Voltage Between ECM Relay Terminal 5 And Ground
    G00781324Courtesy of NISSAN MOTOR CO., U.S.A.

    Voltage: Battery voltage 

    OK or NG 

    1. OK GO TO  10 .
    2. NG GO TO 9.
  9. DETECT MALFUNCTIONING PART 

    Check the following.

    • 10A fuse
    • Harness for open and short between ECM relay and fuse
    1. Repair or replace harness or connectors.
  10. CHECK ECM RELAY 
    1. Apply 12V direct current between ECM relay terminals 1 and 2.
    2. Check continuity between ECM relay terminals 3 and 5, 6 and 7.
      Fig 8: Checking ECM Relay
      G00781325Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK GO TO  20 .
    2. NG Replace ECM relay.
  11. CHECK CONDENSER GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Check harness continuity between condenser terminal 2 and engine ground. Refer to WIRING DIAGRAM  .

      Continuity should exist. 

    3. Also check harness for short to power.

    OK or NG 

    1. OK GO TO 12.
    2. NG Repair open circuit or short to power in harness or connectors.
  12. CHECK CONDENSER 

    Check resistance between condenser terminals 1 and 2.

    Fig 9: Checking Resistance Between Condenser Terminals 1 And 2
    G00781326Courtesy of NISSAN MOTOR CO., U.S.A.

    Resistance: Above 1 Mohm at 25°C (77°F) 

    OK or NG 

    1. OK GO TO 13.
    2. NG Replace condenser.
  13. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-V 
    1. Turn ignition switch OFF.
    2. Reconnect harness connectors disconnected.
    3. Disconnect ignition coil harness connector.
      Fig 10: Identifying Ignition Coil Harness Connector
      G00781327Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Turn ignition switch ON.
    5. Check voltage between ignition coil terminal 3 and ground with CONSULT-II or tester.
      Fig 11: Checking Voltage Between Ignition Coil Terminal 3 And Ground
      G00781328Courtesy of NISSAN MOTOR CO., U.S.A.

    Voltage: Battery voltage 

    OK or NG 

    1. OK GO TO  15 .
    2. NG GO TO 14.
  14. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connector F211, F221 (Ignition coil No. 2, No. 4, No. 6)
    • Harness for open or short between ignition coil and harness connector F22
    1. Repair or replace harness or connectors.
  15. CHECK IGNITION COIL GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Check harness continuity between ignition coil terminal 2 and engine ground. Refer to WIRING DIAGRAM  .

      Continuity should exist. 

    3. Also check harness for short to power.

    OK or NG 

    1. OK GO TO  17 .
    2. NG GO TO 16.
  16. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors F221, F211 (Ignition coil No. 2, No. 4, No. 6)
    • Check the harness for open between ignition coil and ground.
    1. Repair or replace harness or connectors.
  17. CHECK IGNITION COIL OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Disconnect ECM harness connector.
    2. Check harness continuity between ECM terminals 62, 81, 61, 80, 60, 79 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 

    1. OK GO TO  19 .
    2. NG GO TO 18.
  18. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors F211, F221 (Ignition coil No. 2, No. 4, No. 6)
    • Check the harness for open or short between ignition coil and ECM.
    1. Repair open circuit or short to ground or short to power in harness or connectors.
  19. CHECK IGNITION COIL WITH POWER TRANSISTOR 

    Check resistance between ignition coil terminals 2 and 3.

    Fig 12: Checking Resistance Between Ignition Coil Terminals 2 And 3
    G00781329Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK GO TO 20.
    2. NG Replace ignition coil with power transistor.
  20. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT  " .

    1. INSPECTION END 
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