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Diagnostic Procedure

WARNING: This page is about a different car, the 2007 Nissan Quest. However, it is still accessible from the selected car via links, so may be relevant.
  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 PEDAL

      CONDITION INDICATION
      Brake pedal: Slightly depressed OFF
      Brake pedal: Fully released ON
      Fig 1: Consult-II Display - DATA MONITOR
      G04900669Courtesy of NISSAN NORTH AMERICA, INC.

    Without CONSULT-II 

    1. Turn ignition switch ON.
    2. Check voltage between ECM terminal 108 and ground under the following conditions.
      CONNECTOR TERMINAL VOLTAGE SPECIFICATION

      CONDITION VOLTAGE
      Brake pedal: Slightly depressed Approximately 0V
      Brake pedal: Fully released Battery voltage

    OK or NG 

    OK: GO TO 2.

    NG: GO TO  3.

    Fig 2: Checking Voltage Between ECM Terminal 108 And Ground
    G04900670Courtesy of NISSAN NORTH AMERICA, INC.
  2. CHECK OVERALL FUNCTION-II 

    With CONSULT-II 

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

    BRAKE PEDAL

    CONDITION INDICATION
    Brake pedal: Fully released OFF
    Brake pedal: Slightly depressed ON
    Fig 3: CONSULT-II Display - DATA MONITOR
    G04900671Courtesy of NISSAN NORTH AMERICA, INC.

    Without CONSULT-II 

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

    CONNECTOR TERMINAL VOLTAGE SPECIFICATION

    CONDITION VOLTAGE
    Brake pedal: Fully released Approximately 0V
    Brake pedal: Slightly depressed Battery voltage

    OK or NG 

    OK: INSPECTION END 

    NG: GO TO  7.

    Fig 4: Checking Voltage Between ECM Terminal 101 And Ground
    G04895065Courtesy of NISSAN NORTH AMERICA, INC.
  3. 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 5: Identifying ASCD Brake Switch Connector And Stop Lamp Switch
      G04905723Courtesy of NISSAN NORTH AMERICA, INC.
    4. Check voltage between ASCD brake switch terminal 1 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

    OK or NG 

    OK: GO TO  5.

    NG: GO TO 4.

    Fig 6: Checking Voltage Between ASCD Switch Terminal 1 And Ground
    G04875403Courtesy of NISSAN NORTH AMERICA, INC.
  4. 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.

  5. 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 6.

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

  6. CHECK ASCD BRAKE SWITCH 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO  11.

    NG: Replace ASCD brake switch.

  7. CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect stop lamp switch harness connector.
      Fig 7: Identifying ASCD Brake Switch Connector And Stop Lamp Switch
      G04905723Courtesy of NISSAN NORTH AMERICA, INC.
    3. Check voltage between stop lamp switch terminal 1 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

    OK or NG 

    OK: GO TO  9.

    NG: GO TO 8.

    Fig 8: Checking Voltage Between Stop Lamp Switch Terminal 1 And Ground
    G04895061Courtesy of NISSAN NORTH AMERICA, INC.
  8. 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.

  9. 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 10.

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

  10. CHECK STOP LAMP SWITCH 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO 11.

    NG: Replace stop lamp switch.

  11. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    : INSPECTION END 

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