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Home >> Infiniti >> 2005 >> Q45 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - System Testing >> ICC Brake Switch >> Diagnostic Procedure
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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.
      Fig 1: Display Data Monitor Mode
      G02369879Courtesy of NISSAN MOTOR CO., U.S.A.
      BRAKE SW1 INDICATION CONDITIONS

      CONDITION INDICATION
      When brake pedal: Slightly depress OFF
      When brake pedal: Fully released ON

    Without CONSULT-II 

    1. Turn ignition switch ON.
    2. Check voltage between ECM terminal 108 and ground under the following conditions.
      ECM TERMINAL 108 AND GROUND VOLTAGE CHECKING CONDITIONS

      CONDITION VOLTAGE
      When brake pedal: Slightly depress Approximately OV
      When brake pedal: Fully released Battery voltage
      Fig 2: Checking Voltage Between ECM Terminal 108 And Ground
      G02369880Courtesy 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.

    BRAKE SW2 INDICATION CONDITIONS

    CONDITION INDICATION
    When brake pedal: Fully released OFF
    When brake pedal: Slightly depressed ON
    Fig 3: Display Data Monitor Mode
    G02369881Courtesy of NISSAN MOTOR CO., U.S.A.

    Without CONSULT-II 

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

    ECM TERMINAL 101 AND GROUND VOLTAGE CHECKING CONDITIONS

    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
    G02369882Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: INSPECTION END 
    2. NG: GO TO  13.
  3. CHECK DTC WITH ICC UNIT 

    Refer to "TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS ".

    OK or NG 

    1. OK: GO TO 4.
    2. NG: Repair or replace.
  4. CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT-I 
    1. Turn ignition switch OFF.
    2. Disconnect ICC brake switch harness connector.
    3. Turn ignition switch ON.
      Fig 5: Locating ICC Brake Switch
      G02369883Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Check voltage between ICC brake switch terminal 1 and ground with CONSULT-II or tester.
      1. Voltage: Battery voltage 

    OK or NG 

    1. OK: GO TO  10.
    2. NG: GO TO 5.
    Fig 6: Checking Voltage Between ICC Brake Switch Terminal 1 And Ground
    G02369884Courtesy of NISSAN MOTOR CO., U.S.A.
  5. CHECK ICC BRAKE SWITCH CIRCUIT-II 
    1. Turn ignition switch OFF.
    2. Disconnect ICC brake hold relay.
    3. Turn ignition switch ON.
      Fig 7: Locating ICC Brake Hold Relay
      G02369885Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Check voltage between ICC brake hold relay terminal 4 and ground with CONSULT-II or tester.
      1. Voltage: Battery voltage 

    OK or NG 

    1. OK: GO TO  7.
    2. NG: GO TO 6.
    Fig 8: Checking Voltage Between ICC Brake Hold Relay Terminal 4 And Ground
    G02369886Courtesy of NISSAN MOTOR CO., U.S.A.
  6. DETECT MALFUNCTIONING PART 

    Check the following.

    • Fuse block (J/B) No. 1 connector M1
    • 10A fuse
    • Harness connectors M15, E205
    • Harness for open or short between ICC brake hold relay and fuse
      1. Repair open circuit or short to ground or short to power in harness or connectors.
  7. CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT-III 
    1. Turn ignition switch OFF.
    2. Check harness continuity between ICC brake hold relay terminal 3 and ICC brake switch terminal 1. 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  9.
    2. NG: GO TO 8.
  8. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E205, M15
    • Harness connectors M61, M401
    • Harness for open or short between ICC brake hold relay and ICC brake switch
      1. Repair open circuit or short to ground or short to power in harness or connectors.
  9. CHECK ICC BRAKE HOLD RELAY 

    Refer to "COMPONENT INSPECTION ".

    1. OK: GO TO  18.
    2. NG: Replace ICC brake fold relay.
  10. CHECK ICC BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-II 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check harness continuity between ICC brake switch terminal 2 and ECM terminal 108. Refer Wiring Diagram.
      1. Continuity should exist. 
    4. Also check harness for short to ground and short to power.

    OK or NG 

    1. OK: GO TO  12.
    2. NG: GO TO 11.
  11. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M401, M61
    • Harness connectors M135, F105
    • Harness for open or short between ICC brake switch and ECM
      1. Repair open circuit or short to ground or short to power in harness or connectors.
  12. CHECK ICC BRAKE SWITCH 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    1. OK: GO TO  18.
    2. NG: Replace ICC brake switch.
  13. CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect stop lamp switch harness connector.
      Fig 9: Locating Stop Lamp Switch
      G02369887Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between stop lamp switch terminal 3 and ground with CONSULT-II or tester. 
      1. Voltage: Battery voltage 

    OK or NG 

    1. OK: GO TO  15.
    2. NG: GO TO 14.
    Fig 10: Checking Voltage Between Stop Lamp Switch Terminal 3 And Ground
    G02369888Courtesy of NISSAN MOTOR CO., U.S.A.
  14. DETECT MALFUNCTIONING PART 

    Check the following.

    • Fuse block (J/B) No. 1 connector M1
    • 10A fuse
    • Harness connectors M61, M401
    • 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.
  15. 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 4. 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  17.
    2. NG: GO TO 16.
  16. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M401, M61
    • Harness connectors M135, F105
    • Harness for open or short between ECM and stop lamp switch
      1. Repair open circuit or short to ground or short to power in harness or connectors.
  17. CHECK STOP LAMP SWITCH 

    Refer to "COMPONENT INSPECTION "

    OK or NG 

    1. OK: GO TO 18.
    2. NG: Replace stop lamp switch.
  18. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    1. INSPECTION END 
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