ECD SYSTEM (w/o EGR Cooler Bypass Valve) VC Output Circuit

DESCRIPTION

The VC voltage (5 V) is generated in the ECM. The voltage is used to supply power to the throttle body assembly, EGR valve position sensor, turbo pressure sensor, accelerator position sensor and fuel pressure sensor.

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1. CHECK MIL

   
   

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

      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 ignition switch ON and tester ON.

   3. Check the communication between the intelligent tester and ECM.

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

   
   

   B

   GO TO MIL CIRCUIT

   A

3. INSPECT ECM (VC VOLTAGE)

   

   Text in Illustration

   *1	ECM Connector

   
   

   1. Turn the ignition switch ON.

   2. Measure the voltage of the ECM connector.

      Result
      Tester Connection Specified Condition E6-18 (VC) - E6-28 (E2) Voltage is not 5 V

   
   

   NEXT

4. CHECK MIL (THROTTLE POSITION SENSOR)

   
   

   1. Disconnect the T5 throttle position sensor connector.

   2. Turn the ignition switch ON.

   3. Check the MIL.

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

   4. Reconnect the throttle position sensor connector.

   
   

   B

   REPLACE DIESEL THROTTLE BODY ASSEMBLY

   A

5. CHECK MIL (MANIFOLD ABSOLUTE PRESSURE SENSOR)

   
   

   1. Disconnect the T8 manifold absolute pressure sensor connector.

   2. Turn the ignition switch ON.

   3. Check the MIL.

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

   4. Reconnect the manifold absolute pressure sensor connector.

   
   

   B

   REPLACE MANIFOLD ABSOLUTE PRESSURE SENSOR

   A

6. CHECK MIL (ACCELERATOR PEDAL POSITION SENSOR)

   
   

   1. Disconnect the A8 accelerator pedal position sensor connector.

   2. Turn the ignition switch ON.

   3. Check the MIL.

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

   4. Reconnect the accelerator position sensor connector.

   
   

   B

   REPLACE ACCELERATOR PEDAL ASSEMBLY

   A

7. CHECK MIL (EGR VALVE POSITION SENSOR)

   
   

   1. Disconnect the E1 EGR valve position sensor connector.

   2. Turn the ignition switch ON.

   3. Check the MIL.

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

   4. Disconnect the EGR valve position sensor connector.

   
   

   B

   REPLACE EGR VALVE ASSEMBLY

   A

8. CHECK MIL (FUEL PRESSURE SENSOR)

   
   

   1. Disconnect the F16 fuel pressure sensor connector.

   2. Turn the ignition switch ON.

   3. Check the MIL.

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

   4. Reconnect the fuel pressure sensor connector.

   
   

   B

   REPLACE COMMON RAIL ASSEMBLY

   A

9. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND)

   
   
   1. 

      Text in Illustration

      *1	ECM Connector

      Disconnect the T5 throttle position sensor connector.

   2. Disconnect the T8 manifold absolute pressure sensor connector.

   3. Disconnect the F16 fuel pressure sensor connector.

   4. Disconnect the E6 ECM connector.

   5. Measure the resistance of the wire harness connector.

      Standard resistance
      Tester Connection Specified Condition E6-18 (VC) - Body ground 10 kΩ or higher

   6. Reconnect the throttle position sensor connector.

   7. Reconnect the manifold absolute pressure sensor connector.

   8. Reconnect the fuel pressure sensor connector.

   9. Reconnect the ECM connector.

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

   REPLACE ECM