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Home >> Infiniti >> 2009 >> QX56 AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Component Testing >> ICC Brake Switch >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK OVERALL FUNCTION-I

    With CONSULT-III 

    1. Turn ignition switch ON.
    2. Select "BRAKE SW1" in "DATA MONITOR" mode with CONSULT-III.
    3. Check "BRAKE SW1" indication under the following conditions.
      BRAKE SWITCH INDICATION CONDITION

      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.
      VOLTAGE REFERENCE CHART

      CONDITION VOLTAGE
      Brake pedal: Slightly depressed Approximately 0V
      Brake pedal: Fully released Battery voltage

      OK or NG 

      OK: GO TO 2.

      NG: GO TO  3.

      Fig 1: Checking Voltage Between ECM Terminal 108 And Ground
      G06315855Courtesy of NISSAN MOTOR CO., U.S.A.
  2. CHECK OVERALL FUNCTION-II

    With CONSULT-III 

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

    BRAKE SWITCH INDICATION CONDITION

    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.

    VOLTAGE REFERENCE CHART

    CONDITION VOLTAGE
    Brake pedal: Fully released Approximately 0V
    Brake pedal: Slightly depressed Battery voltage
    Fig 2: Checking Voltage Between ECM Terminal 101 And Ground
    G06315856Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: INSPECTION END 

    NG: GO TO  10.

  3. CHECK DTC WITH ICC UNIT

    Refer to CONSULT-III FUNCTION (ICC) .

    OK or NG 

    OK: GO TO 4.

    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 3: Identifying ICC Brake Hold Relay
      G06315857Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Check voltage between ICC brake hold relay terminal 4 and ground with CONSULT-III or tester.

      Voltage: Battery voltage 

      OK or NG 

      OK: GO TO  6.

      NG: GO TO 5.

      Fig 4: Checking Voltage Between ICC Brake Hold Relay Terminal 4 And Ground
      G06315858Courtesy 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

      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 

      OK: GO TO 7.

      NG: Repair open circuit or short to ground or short to power in harness or connectors.

      Fig 5: Identifying ICC Brake And Stop Lamp Switch
      G06315859Courtesy 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 

      OK: GO TO 8.

      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 ".

    OK: GO TO 9.

    NG: Replace ICC brake hold relay.

  9. CHECK ICC BRAKE SWITCH

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO  14.

    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 6: Identifying ICC Brake And Stop Lamp Switch
      G06315860Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between stop lamp switch terminal 3 and ground with CONSULT-III or tester.

      Voltage: Battery voltage 

      OK or NG 

      OK: GO TO  12.

      NG: GO TO 11.

      Fig 7: Checking Voltage Between Stop Lamp Switch Terminal 3 And Ground
      G06315861Courtesy 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

      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 

      OK: GO TO 13.

      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 

    OK: GO TO 14.

    NG: Replace stop lamp switch.

  14. CHECK INTERMITTENT INCIDENT

    Refer to "HOW TO CHECK TERMINAL "and "INTERMITTENT INCIDENT ".

    INSPECTION END 

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