FixVault
Home › Infiniti › 2004 › I35 › Repair and Diagnosis › Engine Performance › System › Engine Control System › Trouble Diagnosis For Power Supply › Main Power Supply And Ground Circuit › Diagnostic Procedure

Diagnostic Procedure

  1. INSPECTION START 

    Start engine

    Is engine running? 

    YES or NO 

    1. YES: GO TO  9 .
    2. NO: GO TO 2.
  2. CHECK ECM POWER SUPPLY CIRCUIT-I 
    1. Turn ignition switch OFF and then ON.
    2. Check voltage between ECM terminal 43 and ground with CONSULT-II or tester.
      Fig 1: Checking Voltage At ECM
      G00786468Courtesy of NISSAN MOTOR CO., U.S.A.

      Voltage: Battery voltage 

      OK or NG 

    1. OK: GO TO  4 .
    2. NG: GO TO 3.
  3. DETECT MALFUNCTIONING PART 

    Check the following.

    • 10A fuse
    • Harness connectors M229, F66
    • Fuse block (J/B) connectors M19, E89
    • Harness for open or short between ECM and ignition switch
    1. : Repair harness or connectors.
  4. CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-I 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check harness continuity between ECM terminals 48, 57, 106, 108 and engine ground.

      Refer to WIRING DIAGRAM.

      Continuity should exist. 

    4. Also check harness for short to power.

      OK or NG 

    1. OK: GO TO 5.
    2. NG: Repair open circuit or short to power in harness or connectors.
  5. CHECK POWER SUPPLY-II 
    1. Disconnect ECM relay.
      Fig 2: Identifying ECM Relay
      G00786469Courtesy of NISSAN MOTOR CO., U.S.A.
    2. Check voltage between ECM relay terminals 2, 6 and ground with CONSULTS-II or tester.
      Fig 3: Checking Voltage At ECM
      G00786470Courtesy of NISSAN MOTOR CO., U.S.A.

      Voltage: Battery voltage 

    OK or NG 

    1. OK: GO TO  7 .
    2. NG: GO TO 6.
  6. DETECT MALFUNCTIONING PART 

    Check the following.

    • 15A fuses
    • Joint connector-13
    • Harness for open or short between ECM relay and battery
    1. : Repair open circuit or short to ground or short to power in harness or connectors.
  7. CHECK OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Check harness continuity between ECM terminal 38 and ECM relay terminal 1. Refer to WIRING DIAGRAM.

      Continuity should exist. 

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

    OK or NG 

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

    Check the following.

    • Harness connectors E15, F18
    • Harness for open or short between ECM relay and ECM
    1. : Repair open circuit or short to ground or short to power in harness or connectors.
  9. CHECK ECM POWER SUPPLY CIRCUIT-II 
    1. Turn ignition switch ON and then OFF.
    2. Check voltage between ECM terminals 110, 112 and ground with CONSULT-II or tester.
      Fig 4: Checking Voltage Between ECM Terminals & Ground
      G00786471Courtesy of NISSAN MOTOR CO., U.S.A.

      Voltage: 

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

      OK or NG 

    1. OK: GO TO  15 .
    2. NG (Battery voltage does not exist.): GO TO 10.
    3. NG (Battery voltage exists for more than a few seconds.): GO TO  12 .
  10. CHECK ECM POWER SUPPLY CIRCUIT-III 
    1. Disconnect ECM relay. See Fig 2 .
    2. Check voltage between ECM relay terminal 3 and ground with CONSULT-II or tester.
      Fig 5: Checking Voltage At ECM
      G00786473Courtesy of NISSAN MOTOR CO., U.S.A.

      Voltage: Battery voltage 

      OK or NG 

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

    Check the following.

    • Joint connector-13
    • Harness for open or short between ECM relay and 15A fuse
    1. : Repair open circuit or short to ground or short to power in harness or connectors.
  12. CHECK HARNESS CONTINUITY BETWEEN ECM RELAY AND ECM FOR OPEN AND SHORT 
    1. Check harness continuity between ECM terminals and ECM relay terminals as follows.

      Refer to WIRING DIAGRAM.

      Fig 6: Displaying ECM And ECM Relay Terminal Numbers
      G00786474Courtesy of NISSAN MOTOR CO., U.S.A.

      Continuity should exist. 

    2. Also check harness for short to ground and 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 E15, F18
    • Harness for open or short between ECM and ECM relay
    1. : Repair open circuit or short to ground or short to power in harness or connectors.
  14. CHECK ECM RELAY 
    1. Apply 12V direct current between ECM relay terminals 1 and 2.
    2. Check continuity between relay terminals 3 and 5, 6 and 7.
      Fig 7: Checking Continuity Between ECM Relay Terminals
      G00786475Courtesy of NISSAN MOTOR CO., U.S.A.

      OK or NG 

    1. OK: GO TO 15.
    2. NG: Replace ECM relay.
  15. CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-II 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check harness continuity between ECM terminals 48, 57, 106, 108 and engine ground.

      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 16.
    2. NG: Repair open circuit or short to ground or short to power in harness or connectors.
  16. CHECK INTERMITTENT INCIDENT 

    Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT  .

    1. NG: INSPECTION END
About FixVault