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Home >> Nissan-Datsun >> 2006 >> Sentra SE-R >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Component Testing (Qr25DE) >> Electrical Load Signal >> Diagnostic Procedure
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Diagnostic Procedure

  1. INSPECTION START 

    Do you have CONSULT-II?

    Yes or No 

    Yes: GO TO  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.
      3. Fig 1: Consult-II DATA MONITOR Display Screen
      G04075263Courtesy of NISSAN MOTOR CO., U.S.A.
    LOAD SIGNAL CONDITION CHART

    Condition LOAD SIGNAL
    Lighting switch: ON at 2nd position ON
    Lighting switch: OFF OFF

    OK or NG 

    OK: GO TO  4.

    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 2: Checking Voltage Between ECM Terminal 84 And Ground
      G04192247Courtesy of NISSAN MOTOR CO., U.S.A.
    VOLTAGE CONDITION CHART

    Condition Voltage
    Lighting switch: ON at 2nd position BATTERY VOLTAGE
    Lighting switch: OFF 0V

    OK or NG 

    OK: GO TO  5.

    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 3: Consult-II DATA MONITOR Display Screen
      G04075263Courtesy of NISSAN MOTOR CO., U.S.A.
    LOAD SIGNAL CONDITION REFERENCE

    Condition LOAD SIGNAL
    Heater fan switch: ON ON
    Heater fan control switch: OFF OFF

    OK or NG 

    OK: GO TO  6.

    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.
      3. Fig 4: Checking Voltage Between ECM Terminal 96 And Ground
      G04192249Courtesy of NISSAN MOTOR CO., U.S.A.
    VOLTAGE CONDITION CHART

    Condition Voltage
    Heater fan switch: ON Approximately 0V
    Heater fan switch: OFF Approximately 5V

    OK or NG 

    OK: GO TO  7.

    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.
      3. Fig 5: Consult-II DATA MONITOR Display Screen
      G04075263Courtesy of NISSAN MOTOR CO., U.S.A.
    LOAD SIGNAL CONDITION CHART

    Condition LOAD SIGNAL
    Rear window defogger switch: ON ON
    Rear window defogger switch: OFF OFF

    OK or NG 

    OK: INSPECTION END 

    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.
      3. Fig 6: Checking Voltage Between ECM Terminal 93 And Ground
      G04192251Courtesy of NISSAN MOTOR CO., U.S.A.
    VOLTAGE CONDITION CHART

    Condition Voltage
    Rear window defogger switch: ON BATTERY VOLTAGE
    Rear window defogger switch: OFF Approximately 0V

    OK or NG 

    OK: INSPECTION END 

    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 

    OK (Models for USA): GO TO  9.

    OK (Models for Canada): GO TO  11.

    NG: Refer to "HEADLAMP (FOR USA) " or "HEADLAMP (FOR CANADA) - DAYTIME LIGHT SYSTEM - ".

  9. CHECK HEADLAMP INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Stop engine and turn ignition switch OFF.
    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 7: Checking Harness Continuity Between ECM Terminal 84 And Lighting Switch Terminal 9, 10
      G04192252Courtesy of NISSAN MOTOR CO., U.S.A.
      CONDITION CONTINUITY REFERENCE

      Condition Continuity
      1 Should exist
      2 Should not exist
    5. Also check harness for short to ground and short to power.

    OK or NG 

    OK: GO TO  19.

    NG: GO TO  10.

  10. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E108, M19
    • Harness connectors M58, F26
    • Diode-3
    • Harness for open or short between ECM and lighting switch

      : 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 and turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Disconnect lighting switch harness connector E115.

      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 8: Checking Harness Continuity Between ECM Terminal 84 And Lighting Switch Terminal 10, Daytime Light Control Unit Terminal 6
      G04192253Courtesy of NISSAN MOTOR CO., U.S.A.
      CONDITION CONTINUITY REFERENCE

      Condition Continuity
      1 Should exist
      2 Should not exist
    5. Also check harness for short to ground and short to power.

    OK or NG 

    OK: GO TO  19.

    NG: GO TO  12.

  12. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E108, M19
    • Harness connectors M58, F26
    • Diode-3
    • Harness for open or short between ECM and lighting switch
    • Harness for open or short between ECM and daytime light control unit

      : Repair open circuit or short to ground or short to power in harness or connectors.

  13. CHECK HEATER FAN SWITCH FUNCTION 
    1. Turn the heater fan switch ON.
    2. Check that heater fan turns properly.

    OK or NG 

    OK: GO TO  14.

    NG: Refer to "TROUBLE DIAGNOSIS "

  14. CHECK HEATER FAN SW INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Disconnect air control harness connector.
    4. Disconnect fan control switch harness connector.
    5. Check harness continuity between ECM terminal 96 and air control terminal 8, fan control switch terminal 6.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

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

    OK or NG 

    OK: GO TO  19.

    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
    • Harness for open or short between ECM and fan control switch

      : Repair open circuit or short to ground or short to power in harness or connectors.

  16. CHECK REAR WINDOW DEFOGGER FUNCTION 
    1. Turn ignition switch OFF.
    2. Turn ON the rear window defogger switch.
    3. Check the rear windshield. Is the rear windshield and door mirror (with heated mirror models) heated up?

    Yes or No 

    Yes: GO TO  17.

    No: Refer to "REAR WINDOW DEFOGGER "

  17. CHECK REAR WINDOW DEFOGGER INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Disconnect ECM harness connector.
    2. Disconnect rear window defogger relay.
    3. Check harness continuity between ECM terminal 93 and rear window defogger relay terminals 5, 7. Refer to WIRING DIAGRAM .

      Continuity should exist. 

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

    OK or NG 

    OK: GO TO  19.

    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.

      : 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 ".

    : INSPECTION END 

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