ECD SYSTEM EDU Power Source Circuit

DESCRIPTION

An injector driver assembly has been adopted to drive the injector assemblies at high speeds. The injector driver assembly has realized high-speed driving under high fuel pressure conditions through the use of a voltage converter sub-assembly that provides a high-voltage, quick-charging system. The ECM constantly monitors the injector driver assembly and stops the engine or cuts off fuel supply to some cylinders if an abnormal condition is detected.

WIRING DIAGRAM

A01CGSWE02

INSPECTION PROCEDURE

Note

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE


  1. CHECK INJECTOR DRIVER ASSEMBLY (POWER SOURCE)


    1. A01CH1QE10
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Injector Driver Assembly)

      Disconnect the injector driver assembly connector.

    2. Turn the ignition switch to ON.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      E26-8 (+B) - E27-1 (GND) Ignition switch ON 18 to 27 V
    4. Reconnect the injector driver assembly connector.


    NG
    OK
  2. INSPECT EDU RELAY


    1. A01CGY9E02

      Remove the EDU relay from the No. 2 relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 - 5 No battery voltage applied to terminals 1 and 2 10 kΩ or higher
      3 - 5 Battery voltage applied to terminals 1 and 2 Below 1 Ω
    3. Reinstall the EDU relay.


    NG
    OK
  3. CHECK HARNESS AND CONNECTOR (EDU RELAY - BATTERY)


    1. Remove the EDU relay from the No. 2 relay block.

    2. Disconnect the negative battery terminal.

    3. Disconnect the positive battery terminal.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      EDU relay terminal 5 - Positive battery terminal Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      EDU relay terminal 5 or Positive battery terminal - Body ground Always 10 kΩ or higher
    5. Reinstall the EDU relay.

    6. Reconnect the positive battery terminal.

    7. Reconnect the negative battery terminal.


    NG
    OK
  4. CHECK HARNESS AND CONNECTOR (EDU RELAY - ENG-3 RELAY)


    1. Remove the EDU relay from the No. 2 relay block.

    2. Remove the ENG-3 relay from the No. 1 relay block.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      EDU relay terminal 1 - ENG-3 relay terminal 3 Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      EDU relay terminal 1 or ENG-3 relay terminal 3 - Body ground Always 10 kΩ or higher
    4. Reinstall the EDU relay.

    5. Reinstall the ENG-3 relay.


    NG
    OK
  5. CHECK HARNESS AND CONNECTOR (EDU RELAY - ECM)


    1. Remove the EDU relay from the No. 2 relay block.

    2. Disconnect the ECM connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      EDU relay terminal 2 - E22-10 (IREL) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      EDU relay terminal 2 or E22-10 (IREL) - Body ground Always 10 kΩ or higher
    4. Reconnect the ECM connector.

    5. Reinstall the EDU relay.


    NG
    OK
  6. CHECK HARNESS AND CONNECTOR (EDU RELAY - INJECTOR DRIVER ASSEMBLY)


    1. Disconnect the EDU relay from the No. 2 relay block.

    2. Disconnect the injector driver assembly connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      EDU relay terminal 3 - E26-8 (+B) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      EDU relay terminal 3 or E26-8 (+B) - Body ground Always 10 kΩ or higher
    4. Reconnect the injector driver assembly connector.

    5. Reinstall the EDU relay.


    NG
    OK
  7. CHECK HARNESS AND CONNECTOR (INJECTOR DRIVER ASSEMBLY - BODY GROUND)


    1. Disconnect the injector driver assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E27-1 (GND) - Body ground Always Below 1 Ω
    3. Reconnect the injector driver assembly connector.


    NG
    OK
  8. CHECK ECM (IREL VOLTAGE)


    1. A01CHARE04
      Text in Illustration
      *1

      Component with harness connected

      (ECM)

      Turn the ignition switch to ON.

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      E22-10 (IREL) - Body ground Ignition switch ON 0 to 2 V

    NG
    OK