СИСТЕМА SFI VC Output Circuit

DESCRIPTION

The ECM constantly uses 5 V 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.

A001CM5E02

When the VC circuit is short-circuited, the microprocessor in the ECM and sensors that are supplied 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

A0019ADE12
*a Throttle Position Sensor
*b Accelerator Pedal Position Sensor
A001B2PE02

PROCEDURE


  1. CHECK MIL


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

      OK
      MIL lights up.

    OK

    SYSTEM OK

    NG

  2. CHECK CONNECTION 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 BODY)


    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 Click here

    B

  4. CHECK MIL (ACCELERATOR PEDAL)


    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 SENSOR ASSEMBLY Click here

    B

  5. 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

  6. 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

  7. CHECK MIL (VVT SENSOR FOR INTAKE SIDE BANK 1)


    1. Disconnect the VVT sensor for intake side 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 BANK 1 Click here

    B

  8. CHECK MIL (VVT SENSOR FOR EXHAUST SIDE BANK 1)


    1. Disconnect the VVT sensor for exhaust side 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 BANK 1 Click here

    B

  9. CHECK MIL (VVT SENSOR FOR INTAKE SIDE BANK 2)


    1. Disconnect the VVT sensor for intake side 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 BANK 2 Click here

    B

  10. CHECK MIL (VVT SENSOR FOR EXHAUST SIDE BANK 2)


    1. Disconnect the VVT sensor for exhaust side 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 BANK 2 Click here

    B

  11. CHECK HARNESS AND CONNECTOR


    1. A0019Q8E02
      *1 ECM Connector

      Disconnect the throttle body connector.

    2. Disconnect the accelerator pedal position sensor connector.

    3. Disconnect the crankshaft position sensor connector.

    4. Disconnect the camshaft position sensor connector.

    5. Disconnect the VVT sensor connectors.

    6. Disconnect the E1, E2 and A14 ECM connectors.

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

      Standard resistance (Check for short)
      Tester Connection Condition Specified Condition
      E2-34 (VCTA) - Body ground Always 10 kΩ or higher
      A14-23 (VCPA) - Body ground Always 10 kΩ or higher
      A14-22 (VCP2) - Body ground Always 10 kΩ or higher
      E1-18 (VC) - Body ground Always 10 kΩ or higher

    OK

    REPLACE ECM Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR