СИСТЕМА ECD ECM Power Source Circuit

DESCRIPTION

When the ignition switch is turned to ON, the battery voltage is applied to terminal IGSW of the ECM. The MREL output signal from ECM causes a current to flow to the coil, closing the contacts of the EFI MAIN1 relay and supplying power to terminal +B, +B2 and +B3 of the ECM.

WIRING DIAGRAM

B007Q30E01

INSPECTION PROCEDURE

Note


  • After replacing the ECM, the new ECM needs registration Click here and initialization Click here.

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

PROCEDURE


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


    1. Disconnect the ECM connector.

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

      Standard Resistance:
      Tester Connection Condition Specified Condition
      D134-21 (E1) - Body ground Always Below 1 Ω

    3. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. CHECK TERMINAL VOLTAGE (IGSW TERMINAL VOLTAGE)


    1. Disconnect the ECM connector.

    2. B007USVE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to ECM)

      Turn the ignition switch to ON.

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

      Standard voltage
      Tester Connection Condition Specified Condition
      B97-6 (IGSW) - Body ground Ignition switch ON 11 to 14 V

    NG

    INSPECT INSTRUMENT PANEL RELAY BLOCK (IG2) Click here

    OK

  3. INSPECT EFI MAIN RELAY


    1. Inspect the EFI MAIN relay Click here.


    NG

    REPLACE EFI MAIN RELAY

    OK

  4. CHECK HARNESS AND CONNECTOR (EFI MAIN RELAY - ECM)


    1. Remove the EFI MAIN relay from the instrument relay block.

    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
      EFI MAIN relay terminal 2 - B97-46 (MREL) Always Below 1 Ω
      EFI MAIN relay terminal 5 - B97-2 (+B) Always Below 1 Ω
      EFI MAIN relay terminal 5 - B97-3 (+B2) Always Below 1 Ω
      EFI MAIN relay terminal 5 - B97-4 (+B3) Always Below 1 Ω
      EFI MAIN relay terminal 2 or B97-46 (MREL) - Body ground and other terminals Always 10 kΩ or higher
      EFI MAIN relay terminal 5 or B97-2 (+B) - Body ground and other terminals Always 10 kΩ or higher
      EFI MAIN relay terminal 5 or B97-3 (+B2) - Body ground and other terminals Always 10 kΩ or higher
      EFI MAIN relay terminal 5 or B97-4 (+B3) - Body ground and other terminals Always 10 kΩ or higher

    4. Reinstall the EFI MAIN relay.

    5. Reconnect the ECM connector.


    OK

    CHECK TERMINAL VOLTAGE (EFI MAIN RELAY) Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  5. CHECK TERMINAL VOLTAGE (EFI MAIN RELAY)


    1. Remove the EFI MAIN relay from the instrument panel relay block.

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

      Standard voltage
      Tester Connection Condition Specified Condition
      EFI MAIN relay terminal 3 - Body ground and other terminals Ignition switch ON 11 to 14 V

    3. Reinstall the EFI MAIN relay.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK HARNESS AND CONNECTOR (EFI MAIN RELAY - BODY GROUND)


    1. Remove the EFI MAIN relay from the instrument panel relay block.

    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
      EFI MAIN relay terminal 1 - Body ground and other terminals Always Below 1 Ω

    4. Reinstall the EFI MAIN relay.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. INSPECT INSTRUMENT PANEL RELAY BLOCK (IG2)


    1. Inspect the instrument panel relay block (IG2 relay).


    NG

    REPLACE INSTRUMENT PANEL RELAY BLOCK (IG2)

    OK

  8. CHECK HARNESS AND CONNECTOR


    1. Disconnect the ECM connector.

    2. Remove the instrument panel relay block.

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

      Standard resistance:
      Tester Connection Condition Specified Condition
      B97-6 (IGSW) - 12B-7 Always Below 1 Ω
      B97-6 (IGSW) or 12B-7 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  9. CHECK TERMINAL VOLTAGE (IG2)


    1. Remove the instrument panel relay block.

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

      Standard voltage
      Tester Connection Condition Specified Condition
      12A-1 - Body ground Always 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  10. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL RELAY BLOCK - BODY GROUND)


    1. Remove the instrument panel relay block.

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

      Standard resistance
      Tester Connection Condition Specified Condition
      12E-4 - Body ground and other terminals Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  11. INSPECT IGNITION OR STARTER SWITCH ASSEMBLY


    1. Inspect the ignition or starter switch assembly Click here.


    NG

    REPLACE IGNITION OR STARTER SWITCH ASSEMBLY Click here

    OK

  12. CHECK HARNESS AND CONNECTOR (IGNITION OR STARTER SWITCH ASSEMBLY - INSTRUMENT PANEL RELAY BLOCK)


    1. Disconnect the ignition or starter switch assembly connector.

    2. Remove the instrument panel relay block.

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

      Standard resistance:
      Tester Connection Condition Specified Condition
      H25-6 (IG2) - 12D-2 Always Below 1 Ω
      H25-6 (IG2) or 12D-2 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - INSTRUMENT PANEL RELAY BLOCK)