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Diagnostic Procedure

WARNING: This page is about a different car, the 2004 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.
      Fig 1: Displaying DATA MONITOR Screen
      G00776093Courtesy of NISSAN MOTOR CO., U.S.A.
      Fig 2: Checking ACSD Brake Switch Conditions
      G00776092Courtesy 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.
      Fig 3: Checking Voltage Between ECM Terminal 108 And Ground
      G00776095Courtesy of NISSAN MOTOR CO., U.S.A.
      Fig 4: Checking ACSD Brake Switch Conditions
      G00776094Courtesy 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 SW2" indication in "DATA MONITOR" mode.

    Fig 5: Displaying Data Monitor Screen
    G00776097Courtesy of NISSAN MOTOR CO., U.S.A.
    Fig 6: Checking ACSD Brake Switch Conditions
    G00776096Courtesy of NISSAN MOTOR CO., U.S.A.

    Without CONSULT-II 

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

    Fig 7: Checking Voltage Between ECM Terminal 101 And Ground
    G00776099Courtesy of NISSAN MOTOR CO., U.S.A.
    Fig 8: Checking ACSD Brake Switch Conditions
    G00776098Courtesy 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.
      Fig 9: Disconnecting ASCD Brake Switch Harness Connector
      G00776100Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Turn ignition switch ON.
    4. Check voltage between ASCD brake switch terminal 1 and ground with CONSULT-II or tester.
      Fig 10: Checking Voltage Between ASCD Brake Switch Terminal 1 And Ground
      G00776101Courtesy of NISSAN MOTOR CO., U.S.A.
      1. Voltage: Battery voltage 

    OK or NG 

    1. OK: GO TO  5 .
    2. 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
      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  .

      1. Continuity should exist. 
    4. Also check harness for short to ground or 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 11: Disconnecting Stop Lamp Switch Harness Connector
      G00776102Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between stop lamp switch terminal 1 and ground with CONSULT -II or tester.
      Fig 12: Checking Voltage Between Stop Lamp Switch Terminal 1 And Ground
      G00776103Courtesy of NISSAN MOTOR CO., U.S.A.
      1. Voltage: Battery voltage 

    OK or NG 

    1. OK: GO TO  9 .
    2. NG: GO TO 8.
  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 fuse
      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  .
      1. 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