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Home >> Nissan-Datsun >> 2012 >> Sentra Base, Standard Trans >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Component Testing (MR20DE) (CALIFORNIA) >> ASCD Brake Switch >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK OVERALL FUNCTION-I

    With CONSULT 

    1. Turn ignition switch ON.
    2. Select "BRAKE SW1" in "DATA MONITOR" mode with CONSULT.
    3. Check "BRAKE SW1" indication under the following conditions.

    M/T models 

    Condition Indication
    Clutch pedal and/or brake pedal: Slightly depressed OFF
    Clutch pedal and brake pedal: Fully released ON

    CVT models 

    Condition Indication
    Brake pedal: Slightly depressed OFF
    Brake pedal: Fully released ON

    Without CONSULT 

    1. Turn ignition switch ON.
    2. Check voltage between ECM terminal 100 and ground under the following conditions.

    M/T models 

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

    CVT models 

    Condition Voltage
    Brake pedal: Slightly depressed Approximately 0 V
    Brake pedal: Fully released Battery voltage
    Fig 1: Checking Overall Function-I
    G04925535Courtesy of NISSAN NORTH AMERICA, INC.

    OK or NG 

    OK: GO TO 2.

    NG: GO TO  3.

  2. CHECK OVERALL FUNCTION-II

    With CONSULT 

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

    Condition Indication
    Brake pedal: Fully released OFF
    Brake pedal: Slightly depressed ON

    Without CONSULT 

    Check voltage between ECM terminal 99 and ground under the following conditions.

    Condition Voltage
    Brake pedal: Fully released Approximately 0 V
    Brake pedal: Slightly depressed Battery voltage
    Fig 2: Checking Overall Function-II
    G04900663Courtesy of NISSAN NORTH AMERICA, INC.

    OK or NG 

    OK: INSPECTION END 

    NG: GO TO  11.

  3. CHECK ASCD BRAKE SWITCH POWER SUPPLY
    1. Turn ignition switch OFF.
    2. Disconnect ASCD brake switch (1) harness connector.
      • Stop lamp switch (2)
      • Brake pedal (3)
    3. Turn ignition switch ON.
      Fig 3: Identifying ASCD Brake Switch, Stop Lamp Switch And Brake Pedal
      G04925533Courtesy of NISSAN NORTH AMERICA, INC.
    4. Check voltage between ASCD brake switch terminal 1 and ground with CONSULT or tester.

    Voltage: Battery voltage 

    Fig 4: Checking ASCD Brake Switch Power Supply
    G04875403Courtesy of NISSAN NORTH AMERICA, INC.

    OK or NG 

    OK: GO TO  8.

    NG (M/T models) >>GO TO 4.

    NG (CVT models) >> GO TO  6.

  4. CHECK ASCD CLUTCH SWITCH POWER SUPPLY CIRCUIT
    1. Turn ignition switch OFF.
    2. Disconnect ASCD clutch switch (1) harness connector.
      • Clutch pedal (2)
    3. Turn ignition switch ON.
      Fig 5: Identifying ASCD Clutch Switch And Clutch Pedal
      G04925539Courtesy of NISSAN NORTH AMERICA, INC.
    4. Check voltage between ASCD clutch switch terminal 1 and ground with CONSULT or tester.

    Voltage: Battery voltage 

    Fig 6: Checking ASCD Clutch Switch Power Supply Circuit
    G04875403Courtesy of NISSAN NORTH AMERICA, INC.

    OK or NG 

    OK: GO TO  7.

    NG: GO TO 5.

  5. DETECT MALFUNCTIONING PART

    Check the following.

    • 10 A 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. DETECT MALFUNCTIONING PART

    Check the following.

    • 10 A 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.

  7. CHECK ASCD CLUTCH SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
    1. Turn ignition switch OFF.
    2. Check harness continuity between ASCD brake switch terminal 1 and ASCD clutch 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  10.

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

  8. 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 100 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 9.

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

  9. CHECK ASCD BRAKE SWITCH

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO  15.

    NG: Replace ASCD brake switch. Refer to , "REMOVAL AND INSTALLATION ".

  10. CHECK ASCD CLUTCH SWITCH

    Refer to "COMPONENT INSPECTION "

    OK or NG 

    OK: GO TO  15.

    NG: Replace ASCD clutch switch. Refer to , "REMOVAL AND INSTALLATION ".

  11. CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT
    1. Turn ignition switch OFF.
    2. Disconnect stop lamp switch (2) harness connector.
      • ASCD brake switch (1)
      • Brake pedal (3)
      Fig 7: Identifying ASCD Brake Switch, Stop Lamp Switch And Brake Pedal
      G04925533Courtesy of NISSAN NORTH AMERICA, INC.
    3. Check voltage between stop lamp switch terminal 1 and ground with CONSULT or tester.
    Fig 8: Checking Stop Lamp Switch Power Supply Circuit
    G04925542Courtesy of NISSAN NORTH AMERICA, INC.

    Voltage: Battery voltage 

    OK or NG 

    OK: GO TO  13.

    NG: GO TO 12.

  12. DETECT MALFUNCTIONING PART

    Check the following.

    • 10 A 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.

  13. CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
    1. Disconnect ECM harness connector.
    2. Check harness continuity between ECM terminal 99 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 14.

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

  14. CHECK STOP LAMP SWITCH

    Refer to "COMPONENT INSPECTION "

    OK or NG 

    OK: GO TO  15.

    NG: Replace stop lamp switch. Refer to , "REMOVAL AND INSTALLATION ".

  15. CHECK INTERMITTENT INCIDENT

    Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .

    INSPECTION END 

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