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Home >> Nissan-Datsun >> 2005 >> 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 

    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: DATA MONITOR, LOAD SIGNAL - CONSULT-II Display Screen
      G02454348Courtesy of NISSAN MOTOR CO., U.S.A.
      LIGHTING SWITCH CONDITIONS AND LOAD SIGNAL REFERENCE

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

    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.
      Fig 2: Checking Voltage Between ECM Connector Terminal 84 And Ground
      G02454349Courtesy of NISSAN MOTOR CO., U.S.A.
      LIGHTING SWITCH CONDITIONS AND VOLTAGE REFERENCE

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

    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.
      Fig 3: DATA MONITOR, LOAD SIGNAL - CONSULT-II Display Screen
      G02454350Courtesy of NISSAN MOTOR CO., U.S.A.
      FAN CONTROL SWITCH CONDITIONS AND LOAD SIGNAL REFERENCE

      Condition LOAD SIGNAL
      FAN control switch: ON in any position ON
      FAN control switch: OFF OFF

    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 4: Checking Voltage Between ECM Connector Terminal 96 And Ground
      G02454351Courtesy of NISSAN MOTOR CO., U.S.A.
      FAN CONTROL SWITCH CONDITIONS AND VOLTAGE REFERENCE

      Condition Voltage
      FAN control switch: ON in any position Approximately 0V
      FAN control switch: OFF Approximately 5V

    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 5: DATA MONITOR, LOAD SIGNAL - CONSULT-II Display Screen
      G02454352Courtesy of NISSAN MOTOR CO., U.S.A.
      REAR WINDOW DEFOGGER SWITCH CONDITIONS AND LOAD SIGNAL REFERENCE

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

    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 6: Checking Voltage Between ECM Connector Terminal 93 And Ground
      G02454353Courtesy of NISSAN MOTOR CO., U.S.A.
      REAR WINDOW DEFOGGER SWITCH CONDITIONS AND VOLTAGE REFERENCE

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

    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 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
      G02454354Courtesy of NISSAN MOTOR CO., U.S.A.
      ECM TERMINAL 84 AND LIGHTING SWITCH TERMINAL 9, 10: CONDITIONS AND 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 

    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 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
      G02454355Courtesy of NISSAN MOTOR CO., U.S.A.
      ECM TERMINAL 84 AND LIGHTING SWITCH TERMINAL 10, DAYTIME LIGHT CONTROL UNIT TERMINAL 6: CONDITIONS AND 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 

    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. Turn the fan control switch ON in any position.
    2. 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. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Disconnect air control harness connector.
    4. Check harness continuity between ECM terminal 96 and air control terminal 8, fan control switch terminal 6

      Refer to WIRING DIAGRAM .

      1. 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.
    • Harness for open or short between ECM and 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. 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 

    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. 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 
      1. Continuity should exist. 
    4. 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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