LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Infiniti >> 2004 >> G35 x >> Repair and Diagnosis >> Engine Performance >> System >> 2004.5 - Engine Control System - Introduction - Sedan >> Power Supply And Ground Circuit >> Diagnostic Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnostic Procedure

  1. INSPECTION START 

    Start engine.

    Is engine running? 

    Yes or No

    1. Yes: GO TO  8.
    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 109 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

    OK or NG

    1. OK: GO TO  4.
    2. NG: GO TO 3.
      Fig 1: Checking Voltage Between ECM Terminal 109 & Ground
      G03324917Courtesy of NISSAN MOTOR CO., U.S.A.
  3. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M72, F102
    • Fuse block (J/B) connector M4
    • 10A fuse
    • Harness for open or short between ECM and fuse
    1. : Repair harness or connectors.
  4. CHECK GROUND CONNECTIONS 
    1. Turn ignition switch OFF.
    2. Loosen and retighten two ground screws on the body. Refer to "GROUND INSPECTION ".
      Fig 2: Checking Ground Connections
      G03324918Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    1. OK: GO TO 5.
    2. NG: Repair or replace ground connections.
  5. CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-I 
    1. Disconnect ECM harness connector.
    2. Check harness continuity between ECM terminals 1, 115, 116 and ground.

      Refer to WIRING DIAGRAM .

      Continuity should exist  .

    3. Also check harness for short to power.

    OK or NG

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

    Check the following.

    • Harness connectors F102, M72
    • Harness for open or short between ECM and ground
    1. : Repair open circuit or short to power in harness or connectors.
  7. CHECK ECM POWER SUPPLY CIRCUIT-II 
    1. Reconnect ECM harness connector.
    2. Turn ignition switch ON.
    3. Check voltage between IPDM E/R terminal 17 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

    OK or NG

    1. OK: Go to "IGNITION SIGNAL ".
    2. NG: GO TO 8.
      Fig 3: Checking Voltage Between IPDM E/R Terminal 17 & Ground
      G03324919Courtesy of NISSAN MOTOR CO., U.S.A.
  8. CHECK ECM POWER SUPPLY CIRCUIT-III 
    1. Turn ignition switch ON and then OFF.
    2. Check voltage between ECM terminals 119, 120 and ground with CONSULT-II or tester.

      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 9.
    3. NG (Battery voltage exists for more than a few seconds.): GO TO  12.
      Fig 4: Checking Voltage Between ECM Terminals 119, 120 & Ground
      G03324920Courtesy of NISSAN MOTOR CO., U.S.A.
  9. CHECK ECM POWER SUPPLY CIRCUIT-IV 
    1. Turn ignition switch OFF.
    2. Check voltage between ECM terminal 111 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

    OK or NG

    1. OK: GO TO 10.
    2. NG: GO TO  12.
      Fig 5: Checking Voltage Between ECM Terminal 111 & Ground
      G03324921Courtesy of NISSAN MOTOR CO., U.S.A.
  10. CHECK ECM POWER SUPPLY CIRCUIT-V 
    1. Disconnect ECM harness connector.
    2. Disconnect IPDM E/R harness connector E7.
    3. Check harness continuity between ECM terminals 119, 120 and IPDM E/R terminal 18.

      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  18.
    2. NG: GO TO 11.
  11. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness or connectors E12, F3
    • Harness for open or short between ECM and IPDM E/R
    1. : Repair open circuit or short to ground or short to power in harness or connectors.
  12. CHECK ECM POWER SUPPLY CIRCUIT-VI 
    1. Disconnect ECM harness connector.
    2. Disconnect IPDM E/R harness connector E9.
    3. Check harness continuity between ECM terminal 111 and IPDM E/R terminal 46.

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

    Check the following.

    • Harness or connectors E11, F2
    • Harness for open or short between ECM and IPDM E/R
    1. : Repair open circuit or short to ground or short to power in harness or connectors.
  14. CHECK 15A FUSE 
    1. Disconnect 15A fuse from IPDM E/R.
    2. Check 15A fuse.

    OK or NG

    1. OK: GO TO  18.
    2. NG: Replace 15A fuse.
  15. CHECK GROUND CONNECTIONS 
    1. Loosen and retighten two ground screws on the body. Refer to "GROUND INSPECTION ".
      Fig 6: Checking Ground Connections
      G03324922Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    1. OK: GO TO 16.
    2. NG: Repair or replace ground connections.
  16. CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-II 
    1. Check harness continuity between ECM terminals 1, 115, 116 and ground.

      Refer to WIRING DIAGRAM .

      Continuity should exist  .

    2. Also check harness for short to power.

    OK or NG

    1. OK: GO TO  18.
    2. NG: GO TO 17.
  17. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness or connectors F102, M72
    • Harness for open or short between ECM and ground
    1. : Repair open circuit or short to power in harness connectors.
  18. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    OK or NG

    1. OK: Replace IPDM E/R. Refer to 2004 IPDM E/R (INTELLIGENT POWER DISTRIBUTION .
    2. NG: Repair open circuit or short to ground or short to power in harness or connectors.
scientia non olet · About LEMON Manuals