LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Nissan-Datsun >> 2009 >> 370Z Base, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - System Component Testing >> ASCD Brake Switch >> Diagnosis Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnosis Procedure

  1. INSPECTION START

    Check which type of transmission the vehicle is equipped with.

    Which type of transmission? 

    A/T models or M/T models and SynchroRev match mode: GO TO 2.

    M/T models without SynchroRev match mode: GO TO  7.

  2. 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.
      TERMINALS VOLTAGE REFERENCE

      ASCD brake switch Ground Voltage
      Connector Terminal
      E109 1 Ground Battery voltage

      Is the inspection result normal? 

      YES: GO TO  4.

      NO: GO TO 3.

  3. DETECT MALFUNCTIONING PART

    Check the following.

    • Fuse block (J/B) connector E103
    • 10 A fuse (No. 3)
    • Harness for open or short between ASCD brake switch and fuse

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

  4. 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.
      TERMINALS CONTINUITY REFERENCE

      ASCD brake switch ECM Continuity
      Connector Terminal Connector Terminal
      E109 2 M107 126 Existed
    4. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO  6.

      NO: GO TO 5.

  5. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E106, M6
    • Harness for open or short between ECM and ASCD brake switch

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

  6. CHECK ASCD BRAKE SWITCH

    Refer to "COMPONENT INSPECTION (ASCD BRAKE SWITCH) "

    Is the inspection result normal? 

    YES: GO TO  15.

    NO: Replace ASCD brake switch.

  7. CHECK ASCD BRAKE SWITCH 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.
      TERMINALS VOLTAGE REFERENCE

      ASCD brake switch Ground Condition Voltage (V)
      Connector Terminal
      E109 1 Ground Brake pedal Slightly depressed Approx. 0
      Fully released Battery voltage

      Is the inspection result normal? 

      YES: GO TO  12.

      NO: GO TO 8.

  8. CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT
    1. Turn ignition switch OFF.
    2. Disconnect clutch pedal position switch harness connector.
    3. Turn ignition switch ON.
    4. Check the voltage between clutch pedal position switch harness connector and ground.
      TERMINALS VOLTAGE REFERENCE

      Clutch pedal position switch Ground Voltage
      Connector Terminal
      E108 1 Ground Battery voltage

      Is the inspection result normal? 

      YES: GO TO  10.

      NO: GO TO 9.

  9. DETECT MALFUNCTIONING PART

    Check the following.

    • Fuse block (J/B) connector E103
    • 10 A fuse (No. 3)
    • Harness for open or short between clutch pedal position switch and fuse

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

  10. CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
    1. Turn ignition switch OFF.
    2. Check the continuity between clutch position switch harness connector and ASCD brake switch harness connector.
      TERMINALS CONTINUITY REFERENCE

      Clutch pedal position switch ASCD brake switch Continuity
      Connector Terminal Connector Terminal
      E108 2 E109 1 Existed
    3. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO 11.

      NO: Repair open circuit, short to ground or short to power in harness or connectors.

  11. CHECK CLUTCH PEDAL POSITION SWITCH

    Refer to "COMPONENT INSPECTION (CLUTCH PEDAL POSITION SWITCH) ".

    Is the inspection result normal? 

    YES: GO TO  15.

    NO: Replace clutch pedal position switch.

  12. 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.
      TERMINALS CONTINUITY REFERENCE

      ASCD brake switch ECM Continuity
      Connector Terminal Connector Terminal
      E109 2 M107 126 Existed
    4. Also check harness for short to ground and short to power.

      Is the inspection result normal? 

      YES: GO TO  14.

      NO: GO TO 13.

  13. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E106, M6
    • Harness for open or short between ECM and ASCD brake switch

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

  14. CHECK ASCD BRAKE SWITCH

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

    Is the inspection result normal? 

    YES: GO TO 15.

    NO: Replace ASCD brake switch.

  15. CHECK INTERMITTENT INCIDENT

    Refer to "INTERMITTENT INCIDENT ".

    INSPECTION END

scientia non olet · About LEMON Manuals