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Diagnostic Procedure

WARNING: This page is about a different car, the 2008 Nissan Maxima. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK OVERALL FUNCTION-I 

    With CONSULT-III 

    1. Turn ignition switch ON.
    2. Select "BRAKE SW 1" in "DATA MONITOR" mode with CONSULT-III
    3. Check "BRAKE SW 1" indication under the following conditions.
    BRAKE PEDAL SPECIFICATION (1 OF 2)

    CONDITION INDICATION
    Brake pedal: Slightly depressed OFF
    Brake pedal: Fully released ON

    Without CONSULT-III 

    1. Turn ignition switch ON.
    2. Check voltage between ECM terminal 108 and ground under the following conditions.
    BRAKE PEDAL SPECIFICATION (2 OF 2)

    CONDITION VOLTAGE
    Brake pedal: Slightly depressed Approximately 0V
    Brake pedal: Fully released Battery voltage
    Fig 1: Checking Voltage Between ECM Terminal 108 And Ground
    G04900670Courtesy 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-III 

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

    BRAKE PEDAL SPECIFICATION (1 OF 2)

    CONDITION INDICATION
    Brake pedal: Fully released OFF
    Brake pedal: Slightly depressed ON

    Without CONSULT-III 

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

    BRAKE PEDAL SPECIFICATION (2 OF 2)

    CONDITION VOLTAGE
    Brake pedal: Fully released Approximately 0V
    Brake pedal: Slightly depressed Battery voltage
    Fig 2: Checking Voltage Between ECM Terminal 101 And Ground Under Following Conditions
    G04895065Courtesy 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 3: Identifying ASCD Brake Switch And Brake Pedal
      G04915728Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Check voltage between ASCD brake switch terminal 1 and ground with CONSULT-III or tester.

      Voltage: Battery voltage 

      5. Fig 4: Checking Voltage Between ASCD Brake Switch Terminal 1 And Ground With CONSULT-III Or Tester
      G04875403Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO  5.

    NG: GO TO  4.

  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  7.

    NG: GO TO  6.

  6. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E25, M90
    • 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 5: Identifying ASCD Brake Switch And Stop Lamp Switch
      G04915737Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between stop lamp switch terminal 1 and ground with CONSULT-III or tester.

      Voltage: Battery voltage 

      4. Fig 6: Checking Voltage Between Stop Lamp Switch Terminal 1 And Ground
      G04900676Courtesy 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 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 E25, M90
    • 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 

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