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Home >> Infiniti >> 2006 >> QX56 AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Component 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.
      BRAKE SW1 INDICATION

      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.
      ECM TERMINAL 108 AND GROUND VOLTAGE

      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 

    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

    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.

    ECM TERMINAL 101 AND GROUND VOLTAGE

    CONDITION VOLTAGE
    Brake pedal: Fully released Approximately 0V
    Brake pedal: Slightly depressed Battery voltage
    Fig 4: Identifying Voltage Between ECM Terminal 101 And Ground
    G04133255Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK : INSPECTION END 
    2. NG : GO TO  10.
  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 HOLD RELAY POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect ICC brake hold relay.
    3. Turn ignition switch ON.
      Fig 5: Identifying ICC Brake Hold Relay
      G04133256Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Check voltage between ICC brake hold relay terminal 4 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

    OK or NG 

    1. OK : GO TO  6.
    2. NG : GO TO 5.
      Fig 6: Identifying Voltage Between ICC Brake Hold Relay Terminal 4 And Ground
      G04133257Courtesy of NISSAN MOTOR CO., U.S.A.
  5. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M31, E152
    • Fuse block (J/B) connector M4
    • 10A fuse
    • 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.
  6. CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect ICC brake switch harness connector.
    3. Check harness continuity between ICC brake hold relay terminal 3 and ICC brake switch terminal 1.

      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 7.
    2. NG : Repair open circuit or short to ground or short to power in harness or connectors.
      Fig 7: Identifying ICC Brake Switch Connector
      G04133258Courtesy of NISSAN MOTOR CO., U.S.A.
  7. CHECK ICC BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Disconnect ECM harness connector.
    2. Check harness continuity between ICC brake switch terminal 2 and ECM terminal 108.

      Refer Wiring Diagram.

      Continuity should exist. 

    3. Also check harness for short to ground and short to power.

    OK or NG 

    1. OK : GO TO 8.
    2. NG : Repair open circuit or short to ground or short to power in harness or connectors.
  8. CHECK ICC BRAKE HOLD RELAY 

    Refer to "COMPONENT INSPECTION ".

    1. OK : GO TO 9.
    2. NG : Replace ICC brake hold relay.
  9. CHECK ICC BRAKE SWITCH 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    1. OK : GO TO  14.
    2. NG : Replace ICC brake switch.
  10. CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT 
    1. Turn ignition switch OFF.
    2. Disconnect stop lamp switch harness connector.
      Fig 8: Identifying Stop Lamp Switch Connector
      G04133259Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between stop lamp switch terminal 3 and ground with CONSULT-II or tester.

      Voltage: Battery voltage 

    OK or NG 

    1. OK : GO TO  12.
    2. NG : GO TO 11.
      Fig 9: Identifying Voltage Between Stop Lamp Switch Terminal 3 And Ground
      G04133260Courtesy of NISSAN MOTOR CO., U.S.A.
  11. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M31, E152
    • Fuse block (J/B) No. 1 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.
  12. 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 .

      Continuity should exist. 

    3. Also check harness for short to ground and short to power.

    OK or NG 

    1. OK : GO TO 13.
    2. NG : Repair open circuit or short to ground or short to power in harness or connectors.
  13. CHECK STOP LAMP SWITCH 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    1. OK : GO TO 14.
    2. NG : Replace stop lamp switch.
  14. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    1. : INSPECTION END 
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