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.

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

WIRING DIAGRAM

PROCEDURE

1. CHECK MIL CONDITION

   
   

   1. Check that the Malfunction Indicator Lamp (MIL) lights up when turning the ignition switch to ON.

      OK
      MIL lights up.

   
   

   OK

   END

   NG

2. CHECK CONNECTION BETWEEN INTELLIGENT TESTER AND ECM

   
   

   1. Connect the intelligent tester to the DLC3.

   2. Turn the ignition switch to ON.

   3. Turn the tester on.

   4. Check for 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 with motor body assembly connector.

   2. Turn the ignition switch to ON.

   3. Check the MIL.

      Result

      Result	Proceed to
      MIL does not illuminate	A
      MIL illuminates	B

   4. Reconnect the throttle with motor body assembly connector.

      Tech Tips

      Perform "Inspection After Repairs" after replacing the throttle with motor body assembly Click here.

   
   

   B

   REPLACE THROTTLE WITH MOTOR BODY ASSEMBLY Click here

   A

4. CHECK MIL (ACCELERATOR PEDAL POSITION SENSOR)

   
   

   1. Disconnect the accelerator pedal position sensor connector.

   2. Turn the ignition switch to ON.

   3. Check the MIL.

      Result

      Result	Proceed to
      MIL does not illuminate	A
      MIL illuminates	B

   4. Reconnect the accelerator pedal position sensor connector.

   
   

   B

   REPLACE ACCELERATOR PEDAL ASSEMBLY (ACCELERATOR PEDAL POSITION SENSOR) Click here

   A

5. CHECK MIL (CAMSHAFT POSITION SENSOR (FOR INTAKE CAMSHAFT))

   
   

   1. Disconnect the camshaft position sensor (for intake camshaft) connector.

   2. Turn the ignition switch to ON.

   3. Check the MIL.

      Result

      Result	Proceed to
      MIL does not illuminate	A
      MIL illuminates	B

   4. Reconnect the camshaft position sensor (for intake camshaft) connector.

   
   

   B

   REPLACE CAMSHAFT POSITION SENSOR (FOR INTAKE CAMSHAFT) Click here

   A

6. CHECK MIL (CAMSHAFT POSITION SENSOR (FOR EXHAUST CAMSHAFT))

   
   

   1. Disconnect the camshaft position sensor (for exhaust camshaft) connector.

   2. Turn the ignition switch to ON.

   3. Check the MIL.

      Result

      Result	Proceed to
      MIL does not illuminate	A
      MIL illuminates	B

   4. Reconnect the camshaft position sensor (for exhaust camshaft) connector.

   
   

   B

   REPLACE CAMSHAFT POSITION SENSOR (FOR EXHAUST CAMSHAFT) Click here

   A

7. CHECK MIL (CRANKSHAFT POSITION SENSOR)

   
   

   1. Disconnect the crankshaft position sensor connector.

   2. Turn the ignition switch to ON.

   3. Check the MIL.

      Result

      Result	Proceed to
      MIL does not illuminate	A
      MIL illuminates	B

   4. Reconnect the crankshaft position sensor connector.

   
   

   B

   REPLACE CRANKSHAFT POSITION SENSOR Click here

   A

8. CHECK MIL (MANIFOLD ABSOLUTE PRESSURE SENSOR)

   
   

   1. Disconnect the manifold absolute pressure sensor connector.

   2. Turn the ignition to ON.

   3. Check the MIL.

      Result

      Result	Proceed to
      MIL does not illuminate	A
      MIL illuminate	B

   4. Reconnect the manifold absolute pressure sensor connector.

   
   

   B

   REPLACE MANIFOLD ABSOLUTE PRESSURE SENSOR Click here

   A

9. CHECK HARNESS AND CONNECTOR (EACH SENSOR - ECM)

   
   

   1. Disconnect the throttle with motor body assembly connector.

   2. Disconnect the accelerator pedal position sensor connector.

   3. Disconnect the camshaft position sensor (for intake camshaft) connector.

   4. Disconnect the camshaft position sensor (for exhaust camshaft) connector.

   5. Disconnect the crankshaft position sensor connector.

   6. Disconnect the manifold absolute pressure sensor connector.

   7. Disconnect the ECM connectors.

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

      Standard Resistance
      for RHD Tester Connection Condition Specified Condition B23-115 (VCTA) - Body ground Always 10 kΩ or higher A58-53 (VCPA) - Body ground Always 10 kΩ or higher A58-56 (VCP2) - Body ground Always 10 kΩ or higher B23-113 (VCV1) - Body ground Always 10 kΩ or higher B23-111 (VCE1) - Body ground Always 10 kΩ or higher B23-109 (VCNE) - Body ground Always 10 kΩ or higher B23-118 (VCPM) - Body ground Always 10 kΩ or higher
      for LHD Tester Connection Condition Specified Condition B22-115 (VCTA) - Body ground Always 10 kΩ or higher A58-53 (VCPA) - Body ground Always 10 kΩ or higher A58-56 (VCP2) - Body ground Always 10 kΩ or higher B22-113 (VCV1) - Body ground Always 10 kΩ or higher B22-111 (VCE1) - Body ground Always 10 kΩ or higher B22-109 (VCNE) - Body ground Always 10 kΩ or higher B22-118 (VCPM) - Body ground Always 10 kΩ or higher

   9. Reconnect the throttle with motor body assembly connector.

   10. Reconnect the accelerator pedal position sensor connector.

   11. Reconnect the camshaft position sensor (for intake camshaft) connector.

   12. Reconnect the camshaft position sensor (for exhaust camshaft) connector.

   13. Reconnect the crankshaft position sensor connector.

   14. Reconnect the manifold absolute pressure sensor connector.

   15. Reconnect the ECM connectors.

   
   

   OK

   REPLACE ECM Click here

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR