SFI SYSTEM VC Output Circuit

DESCRIPTION

The ECM constantly generates 5 V power from the battery voltages supplied to the +B (BATT) terminal to operate the microprocessor. The ECM also provides this power to the sensors through the VC output circuit.

A01EN04E65

When the VC circuit is short-circuited, the microprocessor in the ECM and sensors that are supplied with power through the VC circuit are inactivated because the power is not supplied from the VC circuit. Under this condition, the system does not start up and the MIL does not illuminate even if the system malfunctions.

Tech Tips

Under normal conditions, the MIL is illuminated for several seconds when the engine switch is first turned on (IG). The MIL goes off when the engine is started.

WIRING DIAGRAM

A01EROWE05
A01ENZQE03

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK MIL


    1. Check that the Malfunction Indicator Lamp (MIL) lights up when turning the engine switch on (IG).

      OK
      MIL lights up

    NG

    CHECK COMMUNICATION BETWEEN INTELLIGENT TESTER AND ECM Click here

    OK

    SYSTEM OK

  2. CHECK COMMUNICATION BETWEEN INTELLIGENT TESTER AND ECM


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG) and tester on.

    3. Check the communication between the tester and ECM.

      Result
      Result Proceed to
      Communication is possible A
      Communication is not possible B

    A

    GO TO MIL CIRCUIT Click here

    B

  3. CHECK MIL (THROTTLE POSITION SENSOR)


    1. Disconnect the throttle body connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

      Result
      Result Proceed to
      MIL illuminates A
      MIL does not illuminate B

    A

    REPLACE THROTTLE BODY ASSEMBLY Click here

    B

  4. CHECK MIL (ACCELERATOR PEDAL POSITION SENSOR)


    1. Disconnect the accelerator pedal position sensor connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

      Result
      Result Proceed to
      MIL illuminates A
      MIL does not illuminate B

    A

    REPLACE ACCELERATOR PEDAL POSITION SENSOR Click here

    B

  5. CHECK MIL (AIR SWITCHING VALVE for Bank 1)


    1. Disconnect the air switching valve (for Bank 1) connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

      Result
      Result Proceed to
      MIL illuminates A
      MIL does not illuminate B

    A

    REPLACE AIR SWITCHING VALVE Click here

    B

  6. CHECK MIL (AIR SWITCHING VALVE for Bank 2)


    1. Disconnect the air switching valve (for Bank 2) connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

      Result
      Result Proceed to
      MIL illuminates A
      MIL does not illuminate B

    A

    REPLACE AIR SWITCHING VALVE Click here

    B

  7. CHECK MIL (POWER STEERING OIL PRESSURE SENSOR)


    1. Disconnect the power steering oil pressure sensor connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

      Result
      Result Proceed to
      MIL illuminates A
      MIL does not illuminate B

    A

    REPLACE POWER STEERING OIL PRESSURE SENSOR Click here

    B

  8. CHECK MIL (CAMSHAFT POSITION SENSOR)


    1. Disconnect the camshaft position sensor connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

      Result
      Result Proceed to
      MIL illuminates A
      MIL does not illuminate B

    A

    REPLACE CAMSHAFT POSITION SENSOR Click here

    B

  9. CHECK MIL (CRANKSHAFT POSITION SENSOR)


    1. Disconnect the crankshaft position sensor connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

      Result
      Result Proceed to
      MIL illuminates A
      MIL does not illuminate B

    A

    REPLACE CRANKSHAFT POSITION SENSOR Click here

    B

  10. CHECK MIL (VVT SENSOR for Intake Side of Bank 1)


    1. Disconnect the VVT sensor (for Intake Side of Bank 1) connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

      Result
      Result Proceed to
      MIL illuminates A
      MIL does not illuminate B

    A

    REPLACE VVT SENSOR (for Intake Side of Bank 1) Click here

    B

  11. CHECK MIL (VVT SENSOR for Exhaust Side of Bank 1)


    1. Disconnect the VVT sensor (for Exhaust Side of Bank 1) connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

      Result
      Result Proceed to
      MIL illuminates A
      MIL does not illuminate B

    A

    REPLACE VVT SENSOR (for Exhaust Side of Bank 1) Click here

    B

  12. CHECK MIL (VVT SENSOR for Intake Side of Bank 2)


    1. Disconnect the VVT sensor (for Intake Side of Bank 2) connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

      Result
      Result Proceed to
      MIL illuminates A
      MIL does not illuminate B

    A

    REPLACE VVT SENSOR (for Intake Side of Bank 2) Click here

    B

  13. CHECK MIL (VVT SENSOR for Exhaust Side of Bank 2)


    1. Disconnect the VVT sensor (for Exhaust Side of Bank 2) connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

      Result
      Result Proceed to
      MIL illuminates A
      MIL does not illuminate B

    A

    REPLACE VVT SENSOR (for Exhaust Side of Bank 2) Click here

    B

  14. CHECK HARNESS AND CONNECTOR


    1. Disconnect the throttle body connector.

    2. Disconnect the accelerator pedal position sensor connector.

    3. Disconnect the air switching valve (for Bank 1) connector.

    4. Disconnect the air switching valve (for Bank 2) connector.

    5. Disconnect the power steering oil pressure sensor connector.

    6. Disconnect the camshaft position sensor connector.

    7. Disconnect the crankshaft position sensor connector.

    8. Disconnect the VVT sensor (for Intake Side of Bank 1) connector.

    9. Disconnect the VVT sensor (for Exhaust Side of Bank 1) connector.

    10. Disconnect the VVT sensor (for Intake Side of Bank 2) connector.

    11. Disconnect the VVT sensor (for Exhaust Side of Bank 2) connector.

    12. A01EQW7E11

      Disconnect the ECM connectors.

    13. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition
      C53-80 (VCTA) - Body ground Always 10 kΩ or higher
      A38-57 (VCPA) - Body ground Always 10 kΩ or higher
      A38-59 (VCP2) - Body ground Always 10 kΩ or higher
      C53-66 (VCV2) - Body ground Always 10 kΩ or higher
      C53-67 (VCV1) - Body ground Always 10 kΩ or higher
      for RHD
      Tester Connection Condition Specified Condition
      C54-80 (VCTA) - Body ground Always 10 kΩ or higher
      A53-57 (VCPA) - Body ground Always 10 kΩ or higher
      A53-59 (VCP2) - Body ground Always 10 kΩ or higher
      C54-66 (VCV2) - Body ground Always 10 kΩ or higher
      C54-67 (VCV1) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE ECM Click here