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Diagnosis Procedure

ICC MODELS

  1. CHECK DTC WITH ICC SENSOR INTEGRATED UNIT

    Refer to "SELF-DIAGNOSTIC FUNCTION ".

    OK or NG 

    OK: GO TO 2.

    NG: Repair or replace malfunctioning part.

  2. CHECK STOP LAMP SWITCH CIRCUIT
    1. Turn ignition switch OFF.
    2. Check the stop lamp when depressing and releasing the brake pedal.
    STOP LAMP SWITCH REFERENCE CHART

    Brake pedal Stop lamp
    Fully released Not illuminated
    Slightly depressed Illuminated

    OK or NG 

    OK: GO TO  5.

    NG: GO TO 3.

  3. CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT
    1. Disconnect stop lamp switch (1) harness connector.
      • ICC brake switch (2)
      Fig 1: Identifying ICC Brake Switch And Stop Lamp Switch
      G05210064Courtesy of NISSAN MOTOR CO., U.S.A.
    2. Disconnect ICC brake hold relay (1) harness connector.
      • Vehicle Front
      Fig 2: Identifying ICC Brake Hold Relay Harness Connector
      G05210074Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between stop lamp switch terminal 1 and ground with CONSULT-III or tester.

      Voltage: Battery voltage 

      Fig 3: Checking Voltage Between Stop Lamp Switch Terminal 1 And Ground
      G05210075Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Check voltage between ICC brake hold relay terminal 3 and ground with CONSULT-III or tester.

    Voltage: Battery voltage 

    OK or NG 

    OK: GO TO  5.

    NG: GO TO 4.

    Fig 4: Checking Voltage Between ICC Brake Hold Relay Terminal 3 And Ground
    G05210076Courtesy of NISSAN MOTOR CO., U.S.A.
  4. DETECT MALFUNCTIONING PART

    Check the following.

    • Fuse block (J/B) connector E101
    • 10 A fuse
    • Harness for open or short between battery and stop lamp switch
    • Harness for open or short between battery and ICC brake hold relay

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

  5. CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
    1. Disconnect ECM harness connector.
    2. Check harness continuity between the following;

      ECM terminal 101 and stop lamp switch terminal 2,

      ECM terminal 101 and ICC brake hold relay terminal 5.

      Refer to SYSTEM WIRING DIAGRAMS article.

      Continuity should exist  .

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

    OK or NG 

    OK: GO TO  7.

    NG: GO TO 6.

  6. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E108, M15
    • Harness for open or short between ECM and stop lamp switch
    • Harness for open or short between ECM and ICC brake hold relay

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

  7. CHECK STOP LAMP SWITCH

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO 8.

    NG: Replace stop lamp switch.

  8. CHECK ICC BRAKE HOLD RELAY

    Refer to "COMPONENT INSPECTION ".

    OK: GO TO 9.

    NG: Replace ICC brake hold relay.

  9. CHECK INTERMITTENT INCIDENT

    Refer to "DIAGNOSIS PROCEDURE ".

    INSPECTION END 

    ASCD MODELS

    1. CHECK STOP LAMP SWITCH CIRCUIT
      1. Turn ignition switch OFF.
      2. Check the stop lamp when depressing and releasing the brake pedal.
      STOP LAMP SWITCH REFERENCE CHART

      Brake pedal Stop lamp
      Fully released Not illuminated
      Slightly depressed Illuminated

      OK or NG 

      OK: GO TO  4.

      NG: GO TO 2.

    2. CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT
      1. Disconnect stop lamp switch (1) harness connector.
        • ASCD brake switch (2)
        Fig 5: Identifying ASCD Brake Switch And Stop Lamp Switch
        G05210064Courtesy of NISSAN MOTOR CO., U.S.A.
      2. Check voltage between stop lamp switch terminal 1 and ground with CONSULT-III or tester.

      Voltage: Battery voltage 

      OK or NG 

      OK: GO TO  4.

      NG: GO TO 3.

      Fig 6: Checking Voltage Between Stop Lamp Switch Terminal 1 And Ground
      G05210075Courtesy of NISSAN MOTOR CO., U.S.A.
    3. DETECT MALFUNCTIONING PART

      Check the following.

      • Fuse block (J/B) connector E101
      • 10 A 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.

    4. 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 SYSTEM WIRING DIAGRAMS article.

        Continuity should exist  .

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

      OK or NG 

      OK: GO TO  6.

      NG: GO TO 5.

    5. DETECT MALFUNCTIONING PART

      Check the following.

      • Harness connectors E108, M15
      • Harness for open or short between ECM and stop lamp switch

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

    6. CHECK STOP LAMP SWITCH

      Refer to "COMPONENT INSPECTION ".

      OK or NG 

      OK: GO TO 7.

      NG: Replace stop lamp switch.

    7. CHECK INTERMITTENT INCIDENT

    Refer to "DIAGNOSIS PROCEDURE ".

    INSPECTION END 

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