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Diagnosis Procedure

WARNING: This page is about a different car, the 2009 Nissan Maxima. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT
    1. Turn ignition switch OFF.
    2. Disconnect ASCD brake switch harness connector.
    3. Turn ignition switch ON.
    4. Check the voltage between ASCD brake switch harness connector and ground.
      VOLTAGE SPECIFICATION

      ASCD brake switch Ground Voltage
      Connector Terminal
      E37 1 Ground Battery voltage
      Fig 1: Checking Voltage Between ASCD Brake Switch Harness Connector And Ground
      G05869966Courtesy of NISSAN MOTOR CO., U.S.A.

    Is the inspection result normal? 

    YES: GO TO 3.

    NO: GO TO 2.

  2. DETECT MALFUNCTIONING PART

    Check the following.

    • Fuse block (J/B) connector E6
    • Junction block connectors E44, E46
    • 10 A fuse (No. 3)
    • Harness for open or short between ASCD brake switch and fuse

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

  3. CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check the continuity between ASCD brake switch harness connector and ECM harness connector.
      CONTINUITY CHART

      ASCD brake switch ECM Continuity
      Connector Terminal Connector Terminal
      E37 2 E10 110 Existed
    4. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

    YES: GO TO 5.

    NO: GO TO 4.

  4. DETECT MALFUNCTIONING PART

    Check the following.

    • Junction block connectors E45, E46
    • Harness for open or short between ASCD brake switch and ECM

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

  5. CHECK ASCD BRAKE SWITCH

    Refer to "COMPONENT INSPECTION (ASCD BRAKE SWITCH) ".

    Is the inspection result normal? 

    YES: GO TO 6.

    NO: Replace ASCD brake switch.

  6. CHECK INTERMITTENT INCIDENT

    Refer to "INTERMITTENT INCIDENT ".

    : INSPECTION END