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Diagnostic Procedure

WARNING: This page is about a different car, the 2004 Nissan Quest. However, it is still accessible from the selected car via links, so may be relevant.
  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: Displaying ACTIVE TEST Screen
      G00776011Courtesy of NISSAN MOTOR CO., U.S.A.
    2. Make sure that each circuit produces a momentary engine speed drop.

    OK or NG 

    1. OK: INSPECTION END
    2. NG: GO TO  10 .
  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 an oscilloscope.
      3. Fig 2: Reading Voltage Signal Between ECM Terminals 60, 61, 62, 79, 80, 81 And Ground
      G00776012Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Verify that the oscilloscope screen shows the signal wave as shown below.
      Fig 3: Oscilloscope Screen Showing Signal Wave
      G00776013Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: INSPECTION END
    2. NG: GO TO  10 .
  4. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-I 
    1. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
    2. Check voltage between ECM terminals 119, 120 and ground with CONSULT-II or tester.
      Fig 4: Checking Voltage Between ECM Terminals 119, 120 And Ground
      G00776014Courtesy of NISSAN MOTOR CO., U.S.A.
      1. Voltage: Battery voltage 

    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.
      Fig 5: Disconnecting Condenser Harness Connector
      G00776015Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Turn ignition switch ON.
    4. Check voltage between condenser terminal + and ground with CONSULT-II or tester.
      Fig 6: Checking Voltage Between Condenser Terminal + And Ground
      G00776016Courtesy of NISSAN MOTOR CO., U.S.A.
      1. Voltage: Battery voltage 

    OK or NG 

    1. OK: GO TO  8 .
    2. NG: GO TO 6.
  6. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-III 
    1. Turn ignition switch OFF.
    2. Disconnect IPDM E/R harness connector E122.
    3. Check harness continuity between IPDM E/R terminal 35 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  17 .
    2. NG: GO TO 7.
  7. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E5, F14
    • Harness for open or short between IPDM E/R and condenser
      1. Repair open circuit or short to ground or short to power in harness or connectors.
  8. CHECK CONDENSER GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Check harness continuity between condenser terminal - and engine ground. Refer to WIRING DIAGRAM  .
      1. Continuity should exist. 
    3. Also check harness for short to power.

    OK or NG 

    1. OK: GO TO 9.
    2. NG: Repair open circuit or short to power in harness or connectors.
  9. CHECK CONDENSER 

    Refer to COMPONENT INSPECTION  .

    OK or NG 

    1. OK: GO TO  10 .
    2. NG: Replace condenser.
  10. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-V 
    1. Turn ignition switch OFF.
    2. Reconnect all harness connectors disconnected.
    3. Disconnect ignition coil harness connector.
      Fig 7: Disconnecting Ignition Coil Harness Connector
      G00776017Courtesy 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 8: Checking Voltage Between Ignition Coil Terminal 3 And Ground
      G00776018Courtesy of NISSAN MOTOR CO., U.S.A.
      1. Voltage: Battery voltage 

    OK or NG 

    1. OK: GO TO  12 .
    2. NG: GO TO 11.
  11. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors F43, F201
    • Harness for open or short between ignition coil and harness connector F35
      1. Repair or replace harness or connectors.
  12. 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  .

      1. Continuity should exist. 
    3. Also check harness for short to power.

    OK or NG 

    1. OK: GO TO  14 .
    2. NG: GO TO 13.
  13. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors F201, F43
    • Harness for open or short between ignition coil and engine ground
      1. 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 60, 61, 62, 79, 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  16 .
    2. NG: GO TO 15.
  15. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors F43, F201
    • 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.
  16. CHECK IGNITION COIL WITH POWER TRANSISTOR 

    Refer to COMPONENT INSPECTION  ".

    OK or NG 

    1. OK: GO TO 17.
    2. NG: Replace ignition coil with power transistor.
  17. CHECK INTERMITTENT INCIDENT 

    Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT  .

    1. INSPECTION END 
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