LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Infiniti >> 2006 >> FX45 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Component Testing (VK45DE) >> ASCD Brake Switch >> Diagnostic Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

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.
      INDICATION CONDITIONS

      CONDITION INDICATION
      Brake pedal: Slightly depressed OFF
      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.
      VOLTAGE CONDITIONS

      CONDITION VOLTAGE
      Brake pedal: Slightly depressed Approximately 0V
      Brake pedal: Fully released Battery voltage
      Fig 2: Identifying 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.

    INDICATION CONDITIONS

    CONDITION INDICATION
    Brake pedal: Fully released OFF
    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.

    VOLTAGE CONDITIONS

    CONDITION VOLTAGE
    Brake pedal: Fully released Approximately 0V
    Brake pedal: Slightly depressed Battery voltage
    Fig 4: Identifying Voltage Between ECM Terminal 101 And Ground
    G04075255Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK : INSPECTION END

    NG : GO TO  8.

  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
      G04075256Courtesy 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: Identifying 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 E201
    • 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 or short to power.

    OK or NG 

    OK : GO TO  7.

    NG : GO TO 6.

  6. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E211, M41
    • 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.

  7. CHECK ASCD BRAKE SWITCH 

    Refer to "COMPONENT INSPECTION "

    OK or NG 

    OK : GO TO  13.

    NG : Replace ASCD brake switch.

  8. CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect stop lamp switch harness connector.
      Fig 7: Identifying Stop Lamp Switch
      G04075258Courtesy 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  10.

    NG : GO TO 9.

    Fig 8: Identifying Voltage Between Stop Lamp Switch Terminal 1 And Ground With CONSULT-II Or Tester
    G04075259Courtesy of NISSAN MOTOR CO., U.S.A.
  9. DETECT MALFUNCTIONING PART 

    Check the following.

    • Fuse block (J/B) connector E201
    • 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.

  10. 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  12.

    NG : GO TO 11.

  11. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E211, M41
    • 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.

  12. CHECK STOP LAMP SWITCH 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK : GO TO 13.

    NG : Replace stop lamp switch.

  13. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    : INSPECTION END 

scientia non olet · About LEMON Manuals