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Home >> Nissan-Datsun >> 2005 >> Altima SE-R, Automatic >> Repair and Diagnosis >> Engine Performance >> Engine Control System - VQ35DE >> ASCD Brake Switch >> Diagnostic Procedure
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Diagnostic Procedure

  1. CHECK OVERALL FUNCTION-I 

    With CONSULT-II 

    1. Turn ignition switch ON.
    2. Select "BRAKE SW1" in "DATA MONITOR" mode with CONSULT-II.
    3. Check "BRAKE SW1" indication under the following conditions.
    BRAKE SWITCH INDICATIONS - A/T MODELS

    CONDITION INDICATION
    Brake pedal: Slightly depressed OFF
    Brake pedal: Fully released ON
    BRAKE SWITCH INDICATIONS - M/T MODELS

    CONDITION INDICATION
    Clutch pedal and/or brake pedal: Slightly depressed OFF
    Clutch pedal and brake pedal: Fully released ON
    Fig 1: Consult II Data Monitor Screen
    G02527457Courtesy of NISSAN MOTOR CO., U.S.A.

    Without CONSULT-II 

    1. Turn ignition switch ON.
    2. Check voltage between ECM terminal 108 and ground under the following conditions.
    ECM TERMINAL 108 AND GROUND VOLTAGE A/T MODELS

    CONDITION INDICATION
    Brake pedal: Slightly depressed Approximately 0V
    Brake pedal: Fully released Battery voltage
    ECM TERMINAL 108 AND GROUND VOLTAGE M/T MODELS

    CONDITION INDICATION
    Clutch pedal and/or brake pedal: Slightly depressed Approximately 0V
    Clutch pedal and brake pedal: Fully released Battery voltage
    Fig 2: Checking Voltage Between ECM Terminal 108 And Ground
    G02527458Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    • OK: GO TO 2.
    • NG (M/T models): GO TO  3.
    • NG (A/T models): GO TO  8.
  2. CHECK OVERALL FUNCTION-II 

    With CONSULT-II 

    Check "BRAKE SW2" indication in "DATA MONITOR" mode.

    ASCD BRAKE SWITCH INDICATIONS

    CONDITION INDICATION
    Brake pedal: Fully released Approximately 0V
    Brake pedal: Slightly depressed Battery voltage
    Fig 3: Consult II Data Monitor Screen
    G02527459Courtesy of NISSAN MOTOR CO., U.S.A.

    Without CONSULT-II 

    Check voltage between ECM terminal 101 and ground under the following conditions.

    ECM TERMINAL 101 AND GROUND VOLTAGE

    CONDITION INDICATION
    Clutch pedal and brake pedal: Fully released Approximately 0V
    Clutch pedal and/or brake pedal: Slightly depressed Battery voltage

    OK or NG

    • OK: INSPECTION END 
    • NG: GO TO  13.
    Fig 4: Checking Voltage Between ECM Terminal 101 And Ground
    G02527460Courtesy of NISSAN MOTOR CO., U.S.A.
  3. CHECK ASCD CLUTCH SWITCH CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect ASCD brake switch harness connector.
    3. Turn ignition switch ON.
    4. Check voltage between ASCD brake switch terminal 1 and ground under the following conditions with CONSULT-II or tester.
    Fig 5: Disconnecting ASCD Brake Switch Harness Connector
    G02527461Courtesy of NISSAN MOTOR CO., U.S.A.
    CLUTCH PEDAL CONDITION - VOLTAGE

    CONDITION INDICATION
    Clutch pedal and/or brake pedal: Slightly depressed Approximately 0V
    Clutch pedal and brake pedal: Fully released Battery voltage

    OK or NG

    • OK: GO TO  10.
    • NG: GO TO 4.
    Fig 6: Checking Voltage Between ASCD Brake Switch Terminal 1 And Ground
    G02527462Courtesy of NISSAN MOTOR CO., U.S.A.
  4. CHECK ASCD CLUTCH SWITCH POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect ASCD clutch switch harness connector.
    3. Turn ignition switch ON.
      Fig 7: Disconnecting ASCD Clutch Switch Harness Connector
      G02527463Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Check voltage between ASCD clutch switch terminal 1 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

    Fig 8: Checking Voltage Between ASCD Clutch Switch Terminal 1 And Ground
    G02527464Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    • OK: GO TO  6.
    • NG: GO TO 5.
  5. DETECT MALFUNCTIONING PART 

    Check the following.

    • Fuse block (J/B) connector E30
    • 10A fuse
    • Harness for open or short between ASCD clutch switch and fuse
      • : Repair open circuit or short to ground or short to power in harness or connectors.
  6. CHECK ASCD CLUTCH SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Check harness continuity between ASCD clutch switch terminal 2 and ASCD brake switch terminal 1. Refer to WIRING DIAGRAM .

      Continuity should exist. 

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

    OK or NG

    • OK: GO TO 7.
    • NG: Repair open circuit or short to ground or short to power in harness or connectors.
  7. CHECK ASCD CLUTCH SWITCH 

    Refer to "COMPONENT INSPECTION "

    OK or NG

    • OK: GO TO  18.
    • NG: Replace ASCD clutch switch.
  8. CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect ASCD brake switch harness connector.
    3. Turn ignition switch ON.
      Fig 9: Disconnecting ASCD Brake Switch Harness Connector
      G02527465Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Check voltage between ASCD brake switch terminal 1 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

    Fig 10: Checking Voltage Between ASCD Brake Switch Terminal 1 And Ground
    G02527466Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    • OK: GO TO  10.
    • NG: GO TO 9.
  9. DETECT MALFUNCTIONING PART 

    Check the following.

    • Fuse block (J/B) connector E30
    • 10A fuse
    • Harness for open or short between ASCD brake switch and fuse
      • : Repair open circuit or short to ground or short to power in harness or connectors.
  10. CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check harness continuity between ECM terminal 108 and ASCD brake switch terminal 2.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  12.
    • NG: GO TO 11.
  11. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E21, F34
    • Harness for open or short between ECM and ASCD brake switch
      • : Repair open circuit or short to ground or short to power in harness or connectors.
  12. CHECK ASCD BRAKE SWITCH 

    Refer to "COMPONENT INSPECTION "

    OK or NG

    • OK: GO TO  18.
    • NG: Replace ASCD brake switch.
  13. CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect stop lamp switch harness connector.
      Fig 11: Disconnecting Stop Lamp Switch Harness Connector
      G02527467Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between stop lamp switch terminal 1 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

    Fig 12: Checking Voltage Between Stop Lamp Switch Terminal 1 And Ground
    G02527468Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    • OK: GO TO  15.
    • NG: GO TO 14.
  14. DETECT MALFUNCTIONING PART 

    Check the following.

    • Fuse block (J/B) connector E30
    • 10A fuse
    • Harness for open or short between stop lamp switch and battery
      • : Repair open circuit or short to ground or short to power in harness or connectors.
  15. CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Disconnect ECM harness connector.
    2. Check harness continuity between ECM terminal 101 and stop lamp switch terminal 2. Refer to WIRING DIAGRAM .

      Continuity should exist. 

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

    OK or NG

    • OK: GO TO  17.
    • NG: GO TO 16.
  16. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E28, M7
    • Harness connectors M71, F59
    • Harness for open or short between ECM and stop lamp switch
      • : Repair open circuit or short to ground or short to power in harness or connectors.
  17. CHECK STOP LAMP SWITCH 

    Refer to "COMPONENT INSPECTION "

    OK or NG

    • OK: GO TO 18.
    • NG: Replace stop lamp switch.
  18. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    • : INSPECTION END 
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