ECD SYSTEM (for Swirl Control Valve) ECM Power Source Circuit

DESCRIPTION

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

WIRING DIAGRAM

A01IU3PE03

INSPECTION PROCEDURE

Note


  • When replacing the ECM, the ECM needs Registration and Initialization Click here.

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

Tech Tips

When the ECM must be replaced, before replacing the ECM, perform the "Learning Values Save" function using the GTS. Then after installing the new ECM, perform all of the initialization/registrations for the "Learning Values Write" function by following the instructions shown on the tester display.

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (POWER SOURCE)

    A01IUCIE01
    Text in Illustration
    *1 Engine Room No. 1 Relay Block
    *2 EFI MAIN Relay
    *a

    Front view of wire harness connector

    (to No. 1 Integration Relay)

    1. Remove the No. 1 integration relay from the engine room No. 1 relay block.

    2. Remove the EFI MAIN relay from the engine room No. 1 relay block.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      1C-1 - Body ground Always 11 to 14 V
      5 (EFI MAIN relay holder) - Body ground Always 11 to 14 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1A-2 - Body ground Always Below 1 Ω
      1 (EFI MAIN relay holder) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ENGINE ROOM NO. 1 RELAY BLOCK - BATTERY)

    OK

  2. INSPECT NO. 1 INTEGRATION RELAY (IG2)


    1. Inspect the No. 1 integration relay (IG2) Click here.


    NG

    REPLACE NO. 1 INTEGRATION RELAY

    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 (ENGINE ROOM NO. 1 RELAY BLOCK - ECM)


    1. Disconnect the ECM connector.

    2. Remove the EFI MAIN relay from the engine room No. 1 relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A76-9 (MREL) - 2 (EFI MAIN relay holder) Always Below 1 Ω
      A76-2 (+B) - 3 (EFI MAIN relay holder) Always Below 1 Ω
      A76-14 (+B2) - 3 (EFI MAIN relay holder) Always Below 1 Ω
      A76-1 (+B3) - 3 (EFI MAIN relay holder) Always Below 1 Ω
      A76-9 (MREL) or 2 (EFI MAIN relay holder) - Body ground Always 10 kΩ or higher
      A76-2 (+B) or 3 (EFI MAIN relay holder) - Body ground Always 10 kΩ or higher
      A76-14 (+B2) or 3 (EFI MAIN relay holder) - Body ground Always 10 kΩ or higher
      A76-1 (+B3) or 3 (EFI MAIN relay holder) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. A01IRFQE68
      Text in Illustration
      *a

      Front view of wire harness connector

      (to ECM)

      Disconnect the ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A76-4 (E1) - Body ground Always Below 1 Ω
      A76-5 (E2) - Body ground Always Below 1 Ω
      A76-17 (E3) - Body ground Always Below 1 Ω
      A76-18 (E4) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK HARNESS AND CONNECTOR (IGSW TERMINAL VOLTAGE)

    A01IRFQE66
    Text in Illustration
    *a

    Front view of wire harness connector

    (to ECM)

    1. Disconnect the ECM 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
      A76-37 (IGSW) - Body ground Ignition switch ON 11 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (ECM - NO. 1 INTEGRATION RELAY) Click here

    OK

    REPLACE ECM Click here

  7. CHECK HARNESS AND CONNECTOR (ECM - NO. 1 INTEGRATION RELAY)


    1. Disconnect the ECM connector.

    2. Remove the No. 1 integration relay from the engine room No. 1 relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A76-37 (IGSW) - 1A-4 Always Below 1 Ω
      A76-37 (IGSW) or 1A-4 - Body ground Always 10 kΩ or higher
      Result
      Result Proceed to
      NG A
      OK (w/ Entry and Start System) B
      OK (w/o Entry and Start System) C

    B

    CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - NO. 1 INTEGRATION RELAY) Click here

    C

    CHECK HARNESS AND CONNECTOR (IGNITION SWITCH ASSEMBLY - NO. 1 INTEGRATION RELAY) Click here

    A

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  8. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - NO. 1 INTEGRATION RELAY)


    1. Disconnect the power management control ECU connector.

    2. Remove the No. 1 integration relay from the engine room No. 1 relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H70-8 (IG2D) - 1A-3 Always Below 1 Ω
      H70-8 (IG2D) or 1A-3 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    GO TO ENTRY AND START SYSTEM Click here

  9. CHECK HARNESS AND CONNECTOR (IGNITION SWITCH ASSEMBLY - NO. 1 INTEGRATION RELAY)


    1. Disconnect the ignition switch assembly connector.

    2. Remove the No. 1 integration relay from the engine room No. 1 relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H6-6 (IG2) - 1A-3 Always Below 1 Ω
      H6-6 (IG2) or 1A-3 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  10. INSPECT IGNITION SWITCH ASSEMBLY


    1. Inspect the ignition switch assembly Click here.


    NG

    REPLACE IGNITION SWITCH ASSEMBLY Click here

    OK

    REPAIR OR REPLACE HARNESS OR CONNECTOR (IGNITION SWITCH ASSEMBLY - BATTERY)