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Home >> Nissan-Datsun >> 2004 >> Sentra SE-R >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Qr25DE >> Electrical Load Signal >> Diagnostic Procedure
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Diagnostic Procedure

  1. INSPECTION START 

    Do you have CONSULT-II?

    Yes or No 

    1. Yes: GO TO 2.
    2. No: GO TO  3.
  2. CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-1 

    WITH CONSULT-II 

    1. Turn ignition switch ON.
    2. Check "LOAD SIGNAL" in "DATA MONITOR" mode with CONSULT-II under the following conditions.
    Fig 1: Displaying Data Monitor Mode With Consult-II
    G00779608Courtesy of NISSAN MOTOR CO., U.S.A.
    Fig 2: Condition & Load Signal Table
    G00779607Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO  4.
    2. NG: GO TO  8.
  3. CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-1 

    WITHOUT CONSULT-II 

    1. Turn ignition switch ON.
    2. Check voltage between ECM terminal 84 and ground under the following conditions.
      3. Fig 3: Checking Voltage Between ECM Terminal 84 & Ground
      G00779610Courtesy of NISSAN MOTOR CO., U.S.A.
      Fig 4: Voltage & Condition Table
      G00779609Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO  5.
    2. NG: GO TO  8.
  4. CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-2 

    WITH CONSULT-II 

    1. Turn ignition switch ON.
    2. Check "LOAD SIGNAL" in "DATA MONITOR" mode with CONSULT-II under the following conditions.
      3. Fig 5: Displaying Data Monitor Mode With Consult-II
      G00779612Courtesy of NISSAN MOTOR CO., U.S.A.
      Fig 6: Condition & Load Signal Table
      G00779611Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO  6.
    2. NG: GO TO  13.
  5. CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-2 

    WITHOUT CONSULT-II 

    1. Turn ignition switch ON.
    2. Check voltage between ECM terminal 96 and ground under the following conditions.
    Fig 7: Checking Voltage Between ECM Terminal 96 & Ground
    G00779614Courtesy of NISSAN MOTOR CO., U.S.A.
    Fig 8: Voltage & Condition Table
    G00779613Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO  7.
    2. NG: GO TO  13.
  6. CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-3 

    WITH CONSULT-II 

    1. Turn ignition switch ON.
    2. Check "LOAD SIGNAL" in "DATA MONITOR" mode with CONSULT-II under the following conditions.
    Fig 9: Displaying Data Monitor Mode With Consult-II
    G00779616Courtesy of NISSAN MOTOR CO., U.S.A.
    Fig 10: Condition & Load Signal Table
    G00779615Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: INSPECTION END.
    2. NG: GO TO  16.
  7. CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-3 

    WITHOUT CONSULT-II 

    1. Turn ignition switch ON.
    2. Check voltage between ECM terminal 93 and ground under the following conditions.
    Fig 11: Checking Voltage Between ECM Terminal 93 & Ground
    G00779618Courtesy of NISSAN MOTOR CO., U.S.A.
    Fig 12: Condition & Voltage Table
    G00779617Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: INSPECTION END.
    2. NG: GO TO  16.
  8. CHECK HEADLAMP FUNCTION 
    1. Start engine.
    2. Turn the lighting switch ON at 2nd position.
    3. Check that headlamps are illuminated.

    OK or NG 

    1. OK (Models for USA): GO TO 9.
    2. OK (Models for Canada): GO TO  11.
    3. NG: Refer to HEADLAMP (FOR USA) or HEADLAMP (FOR CANADA) - DAYTIME RUNNING SYSTEM - .
  9. CHECK HEADLAMP INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Stop engine.
    2. Disconnect ECM harness connector.
    3. Disconnect lighting switch harness connectors.
    4. Check harness continuity between ECM terminal 84 and lighting switch terminal 9, 10 under the following conditions.
      Fig 13: Checking Harness Continuity Between ECM Terminal 84 & Lighting Switch Terminals 9, 10
      G00779619Courtesy of NISSAN MOTOR CO., U.S.A.
      Fig 14: Continuity & Condition Table
      G00779620Courtesy of NISSAN MOTOR CO., U.S.A.
    5. Also check harness for short to ground and short to power.

    OK or NG 

    1. OK: GO TO  19.
    2. NG: GO TO 10.
  10. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E108, M19
    • Harness connectors M58, F26
    • Diode M55
    • Harness for open and short between ECM and lighting switch
      1. Repair open circuit or short to ground or short to power in harness or connectors.
  11. CHECK HEADLAMP INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Stop engine.
    2. Disconnect ECM harness connector.
    3. Disconnect lighting switch harness connector E114.

      Disconnect daytime light control unit harness connector.

    4. Check harness continuity between ECM terminal 84 and lighting switch terminal 10, daytime light control unit terminal 6 under the following conditions.
      Fig 15: Checking Continuity Between ECM & Lighting Switch Terminal 10, Daytime Light Control Unit Terminal 6
      G00779621Courtesy of NISSAN MOTOR CO., U.S.A.
      Fig 16: Continuity & Condition Table
      G00779622Courtesy of NISSAN MOTOR CO., U.S.A.
    5. Also check harness for short to ground and short to power.

    OK or NG 

    1. OK: GO TO  19.
    2. NG: GO TO 12.
  12. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E108, M19
    • Harness connectors M58, F26
    • Diode M55
    • Harness for open and short between ECM and lighting switch
    • Harness for open and short between ECM and daytime light control unit
    • Harness for open and short between daytime light control unit and lighting switch
      1. Repair open circuit or short to ground or short to power in harness or connectors.
  13. CHECK HEATER FAN SWITCH FUNCTION 
    1. Start engine.
    2. Turn the heater fan switch ON in any position.
    3. Check that heater fan turns properly.

    OK or NG 

    1. OK: GO TO 14.
    2. NG: Refer to TROUBLE DIAGNOSIS .
  14. CHECK HEATER FAN INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Stop engine.
    2. Disconnect ECM harness connector.
    3. Disconnect air control connector.
    4. Check harness continuity between ECM terminal 96 and air control terminal 8, fan control switch terminal 6.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

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

    OK or NG 

    1. OK: GO TO  19.
    2. NG: GO TO 15.
  15. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M59, F27
    • Harness for open or short between ECM and air control, fan control switch
      1. Repair open circuit or short to ground or short to power in harness or connectors.
  16. CHECK REAR WINDOW DEFOGGER FUNCTION 
    1. Start engine.
    2. Turn ON the rear window defogger switch.
    3. Check the rear windshield. Is the rear windshield heated up?

    Yes or No 

    1. Yes: GO TO 17.
    2. No: Refer to "REAR WINDOW DEFOGGER ".
  17. CHECK REAR WINDOW DEFOGGER INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Stop engine.
    2. Disconnect ECM harness connector.
    3. Disconnect rear window defogger relay.
    4. Check harness continuity between ECM terminal 93 and rear window defogger relay terminals 5, 7. Refer to WIRING DIAGRAM .

      Continuity should exist. 

    5. 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 B1, M14
    • Harness connectors M58, F26
    • Harness for open or short between ECM and rear window defogger relay.
      1. Repair open circuit or short to ground or short to power in harness or connectors.
  19. CHECK INTERMITTENT INCIDENT 

    Perform "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    1. INSPECTION END 
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