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Diagnostic Procedure

WARNING: This page is about a different car, the 2005 Nissan Titan. 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 SW 1" in "DATA MONITOR" mode with CONSULT-II.
    3. Check "BRAKE SW 1" indication under the following conditions.
      CONDITION INDICATION

      CONDITION INDICATION
      Brake pedal: Slightly depressed OFF
      Brake pedal: Fully released ON
      Fig 1: Displaying "DATA MONITOR" Mode
      G03602061Courtesy 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 SPECIFICATION

      CONDITION VOLTAGE
      Brake pedal: Slightly depressed Approximately 0V
      Brake pedal: Fully released Battery voltage
      Fig 2: Checking Voltage Between ECM Terminal 108 And Ground
      G03602062Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO 2.
    2. NG: GO TO  3.
  2. CHECK OVERALL FUNCTION-II 

    With CONSULT-II 

    Check "BRAKE SW 2" indication in "DATA MONITOR" mode.

    CONDITION INDICATION

    CONDITION INDICATION
    Brake pedal: Fully released OFF
    Brake pedal: Slightly depressed ON
    Fig 3: Displaying "DATA MONITOR" Mode
    G03602063Courtesy of NISSAN MOTOR CO., U.S.A.

    Without CONSULT-II 

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

    VOLTAGE SPECIFICATION

    CONDITION VOLTAGE
    Brake pedal: Fully released Approximately 0V
    Brake pedal: Slightly depressed Battery voltage
    Fig 4: Checking Voltage Between ECM Terminal 101 And Ground
    G03602064Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: INSPECTION END 
    2. 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: Disconnecting ASCD Brake Switch Harness Connector
      G03602065Courtesy 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 

    1. OK: GO TO  5.
    2. NG: GO TO 4.
      Fig 6: Checking Voltage Between ASCD Brake Switch Terminal 1 And Ground
      G03602066Courtesy of NISSAN MOTOR CO., U.S.A.
  4. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M31, E152
    • Fuse block (J/B) connector M4
    • 10A fuse
    • Harness for open or short between ASCD brake switch and fuse
    1. : 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 

    1. OK: GO TO 6.
    2. 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 

    1. OK: GO TO  11.
    2. 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: Disconnecting Stop Lamp Switch Harness Connector
      G03602067Courtesy 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 

    1. OK: GO TO  9.
    2. NG: GO TO 8.
      Fig 8: Checking Voltage Between Stop Lamp Switch Terminal 1 And Ground
      G03602068Courtesy of NISSAN MOTOR CO., U.S.A.
  8. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M31, E152
    • Fuse block (J/B) connector M60
    • 10A fuse
    • Harness for open or short between stop lamp switch and battery
    1. : 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 

    1. OK: GO TO 10.
    2. 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 

    1. OK: GO TO 11.
    2. NG: Replace stop lamp switch.
  11. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    1. : INSPECTION END 
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