SFI SYSTEM 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.

A01CE1IE01

When the VC circuit is short-circuited, the microprocessor in the ECM and sensors that receive power through the VC circuit are deactivated 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

A01CBO6E05

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 CONNECTION BETWEEN INTELLIGENT TESTER AND ECM Click here

    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

  2. CHECK CONNECTION BETWEEN INTELLIGENT TESTER AND ECM


    1. Connect the intelligent tester to the DLC3.

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

    3. Check the communication between the tester and ECM.

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

    B

    GO TO MIL CIRCUIT Click here

    A

  3. CHECK MIL (THROTTLE POSITION SENSOR)


    1. Disconnect the throttle position sensor connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

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

    4. Reconnect the throttle position sensor connector.


    B

    REPLACE THROTTLE WITH MOTOR BODY ASSEMBLY Click here

    A

  4. CHECK MIL (ACCELERATOR PEDAL SENSOR ASSEMBLY)


    1. Disconnect the accelerator pedal position sensor assembly connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

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

    4. Reconnect the accelerator pedal position sensor assembly connector.


    B

    REPLACE ACCELERATOR PEDAL SENSOR ASSEMBLY Click here

    A

  5. CHECK MIL (BATTERY CURRENT SENSOR ASSEMBLY)


    1. Disconnect the battery current sensor assembly connector.

    2. Turn the engine switch on (IG).

    3. Check the MIL.

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

    4. Reconnect the battery current sensor assembly connector.


    B

    REPLACE BATTERY CURRENT SENSOR ASSEMBLY Click here

    A

  6. CHECK HARNESS AND CONNECTOR (THROTTLE POSITION SENSOR - ECM)


    1. Disconnect the throttle position sensor connector.

    2. Disconnect the ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D41-67 (VCTA) or D26-5 (VC) - Body ground Always 10 kΩ or higher

    4. Reconnect the throttle position sensor connector.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (THROTTLE POSITION SENSOR - ECM)

    OK

  7. CHECK HARNESS AND CONNECTOR (ACCELERATOR PEDAL POSITION SENSOR ASSEMBLY - ECM)


    1. Disconnect the accelerator pedal position sensor assembly connector.

    2. Disconnect the ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A8-58 (VCP2) or A3-1 (VCP2) - Body ground Always 10 kΩ or higher
      A8-57 (VCPA) or A3-4 (VCPA) - Body ground Always 10 kΩ or higher

    4. Reconnect the accelerator pedal position sensor assembly connector.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ACCELERATOR PEDAL POSITION SENSOR ASSEMBLY - ECM)

    OK

  8. CHECK HARNESS AND CONNECTOR (BATTERY CURRENT SENSOR ASSEMBLY - ECM)


    1. Disconnect the battery current sensor assembly connector.

    2. Disconnect the ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D41-69 (VCIB) or A2-2 (VC5) - Body ground Always 10 kΩ or higher

    4. Reconnect the battery current sensor assembly connector.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY CURRENT SENSOR ASSEMBLY - ECM)

    OK

    REPLACE ECM Click here