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Diagnostic Procedure

WARNING: This page is about a different car, the 2006 Nissan Pathfinder. 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 SWITCH 1 INDICATION

    CONDITION INDICATION
    When brake pedal: Slightly depressed OFF
    When brake pedal: Fully released ON
    Fig 1: Consult-II DATA MONITOR Display Screen
    G04075136Courtesy 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 AND GROUND VOLTAGE

    CONDITION VOLTAGE
    When brake pedal: Slightly depressed Approximately 0V
    When brake pedal: Fully released Battery voltage
    Fig 2: Checking Voltage Between Ground And ECM Terminal 108
    G04075137Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO 2.

    NG: GO TO  3.

  2. CHECK OVERALL FUNCTION-II 

    With CONSULT-II 

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

    BRAKE SWITCH 2 INDICATION

    CONDITION INDICATION
    When brake pedal: Fully released OFF
    When brake pedal: Slightly depressed ON
    Fig 3: Consult-II DATA MONITOR Display Screen
    G04075138Courtesy of NISSAN MOTOR CO., U.S.A.

    Without CONSULT-II 

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

    ECM TERMINAL AND GROUND VOLTAGE

    CONDITION VOLTAGE
    When brake pedal: Fully released Approximately 0V
    When brake pedal: Slightly depressed Battery voltage
    Fig 4: Checking Voltage Between ECM Terminal 101 And Ground
    G04173780Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: INSPECTION END 

    NG: GO TO  7.

  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: View Of ASCD Brake Switch & Stop Lamp Switch
      G04147624Courtesy 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 

    OK or NG 

    OK: GO TO  5.

    NG: GO TO 4.

    Fig 6: Checking Voltage Between Connector Terminal 1 and Ground
    G04075143Courtesy of NISSAN MOTOR CO., U.S.A.
  4. DETECT MALFUNCTIONING PART 

    Check the following.

    • Fuse block (J/B) connector E160
    • 10A fuse
    • Harness for open or short between ASCD brake switch and fuse

    : Repair open circuit or short to ground 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: View Of ASCD Brake Switch & Stop Lamp Switch
      G04147624Courtesy 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 

    OK or NG 

    OK: GO TO  9.

    NG: GO TO 8.

    Fig 8: Checking Voltage Between Stop Lamp Switch Terminal 1 And Ground
    G04173784Courtesy of NISSAN MOTOR CO., U.S.A.
  8. DETECT MALFUNCTIONING PART 

    Check the following.

    • Fuse block (J/B) connector E160
    • 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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