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.

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.

WIRING DIAGRAM

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.

   
   

   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

   4. Reconnect the throttle body connector.

   
   

   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

   4. Reconnect the accelerator pedal position sensor connector.

   
   

   A

   REPLACE ACCELERATOR PEDAL ASSEMBLY Click here

   B

5. CHECK MIL (CRANKSHAFT POSITION SENSOR)

   
   

   1. Disconnect the crankshaft position sensor.

   2. Turn the engine switch on (IG).

   3. Check the MIL.

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

   4. Reconnect the crankshaft position sensor.

   
   

   A

   REPLACE CRANKSHAFT POSITION SENSOR Click here

   B

6. CHECK MIL (CAMSHAFT POSITION SENSOR)

   
   

   1. Disconnect the camshaft position sensor.

   2. Turn the engine switch on (IG).

   3. Check the MIL.

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

   4. Reconnect the camshaft position sensor.

   
   

   A

   REPLACE CAMSHAFT POSITION SENSOR Click here

   B

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

   
   

   1. Remove the air cleaner assembly LH.

   2. Disconnect the VVT sensor for intake side bank 1 connector.

   3. Turn the engine switch on (IG).

   4. Check the MIL.

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

   5. Reconnect the VVT sensor for intake camshaft bank 1 connector.

   
   

   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

   4. Reconnect the VVT sensor for exhaust side bank 1 connector.

   
   

   A

   REPLACE VVT SENSOR FOR EXHAUST SIDE BANK 1 Click here

   B

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

   
   

   1. Remove the air cleaner assembly RH.

   2. Disconnect the VVT sensor for intake side bank 2 connector.

   3. Turn the engine switch on (IG).

   4. Check the MIL.

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

   5. Reconnect the VVT sensor for intake camshaft bank 2 connector.

   
   

   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

    4. Reconnect the VVT sensor for exhaust side bank 2 connector.

    
    

    A

    REPLACE VVT SENSOR FOR EXHAUST SIDE BANK 2 Click here

    B

11. CHECK MIL (FUEL PRESSURE SENSOR)

    
    

    1. Remove the intake manifold Click here.

    2. Disconnect the fuel pressure sensor connector.

    3. Turn the engine switch on (IG).

    4. Check the MIL.

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

    5. Reconnect the fuel pressure sensor connector.

    
    

    A

    REPLACE FUEL PRESSURE SENSOR Click here

    B

12. CHECK HARNESS AND CONNECTOR

    
    

    1. 

       Disconnect the throttle body connector.

    2. Disconnect the accelerator pedal position sensor connector.

    3. Disconnect the canister pump module connector.

    4. Disconnect the VVT sensor for intake side (bank 1).

    5. Disconnect the VVT sensor for exhaust side (bank 1).

    6. Disconnect the VVT sensor for intake side (bank 2).

    7. Disconnect the VVT sensor for exhaust side (bank 2).

    8. Disconnect the crankshaft position sensor.

    9. Disconnect the fuel pressure sensor.

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

    11. 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

    12. Reconnect the ECM connectors.

    13. Reconnect the accelerator pedal position sensor connector.

    14. Reconnect the throttle body connector.

    15. Reconnect the VVT sensor for intake side (bank 1).

    16. Reconnect the VVT sensor for exhaust side (bank 1).

    17. Reconnect the VVT sensor for intake side (bank 2).

    18. Reconnect the VVT sensor for exhaust side (bank 2).

    19. Reconnect the crankshaft position sensor.

    20. Reconnect the camshaft position sensor.

    21. Reconnect the fuel pressure sensor.

    
    

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE ECM Click here