SFI SYSTEM 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 and +B2 of the ECM.

WIRING DIAGRAM

A005M31E04
A005M31E05

CAUTION / NOTICE / HINT

Note

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

PROCEDURE


  1. INSPECT NO. 1 INTEGRATION RELAY (POWER SOURCE)

    A005J13E02
    Text in Illustration
    *a

    Front view of wire harness connector

    (to No. 1 integration relay)

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

    2. 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

    3. Reinstall the No. 1 integration relay.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (NO. 1 INTEGRATION RELAY - BATTERY)

    OK

  2. INSPECT NO. 1 INTEGRATION RELAY (EFI MAIN RELAY AND IG2 RELAY)

    A005M2YE02
    Text in Illustration
    *a

    Component without harness connected

    (No. 1 integration relay)

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

    2. Disconnect the No. 1 integration relay connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1C-1 - 1D-9 Battery voltage not applied 10 kΩ or higher
      Battery voltage applied to terminals 1D-17 and 1E-10 Below 1 Ω
      1C-1 - 1E-4 Battery voltage not applied 10 kΩ or higher
      Battery voltage applied to terminals 1D-7 and 1E-10 Below 1 Ω

    4. Reconnect the No. 1 integration relay connectors.

    5. Reinstall No. 1 integration relay.


    NG

    REPLACE NO. 1 INTEGRATION RELAY Click here

    OK

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


    1. Remove the No. 1 integration relay from the engine room main 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
      A58-46 (MREL) - 1D-7 Always Below 1 Ω
      A58-2 (+B) - 1E-4 Always Below 1 Ω
      A58-3 (+B2) - 1E-4 Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      A58-46 (MREL) or 1D-7 - Body ground Always 10 kΩ or higher
      A58-2 (+B) or 1E-4 - Body ground Always 10 kΩ or higher
      A58-3 (+B2) or 1E-4 - Body ground Always 10 kΩ or higher

    4. Reinstall the No. 1 integration relay.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. 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
      for RHD
      Tester Connection Condition Specified Condition
      B23-16 (E1) - Body ground Always Below 1 Ω
      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition
      B22-16 (E1) - Body ground Always Below 1 Ω

    3. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. INSPECT ECM (IGSW TERMINAL VOLTAGE)

    A005M9ZE01
    Text in Illustration
    *a

    Front view of wire harness connector

    (to ECM)
    *b for RHD
    *c for LHD

    1. Disconnect the ECM connectors.

    2. Turn the ignition switch to ON.

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

      Standard Voltage
      for RHD
      Tester Connection Switch Condition Specified Condition
      A58-37 (IGSW) - B23-16 (E1) Ignition switch ON 11 to 14 V
      for LHD
      Tester Connection Switch Condition Specified Condition
      A58-37 (IGSW) - B22-16 (E1) Ignition switch ON 11 to 14 V
      Result
      Result Proceed to
      Outside standard range A
      Within standard range B

    4. Reconnect the ECM connectors.


    B

    REPLACE ECM Click here

    A

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


    1. Remove the No. 1 integration relay from the engine room main 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
      A58-37 (IGSW) - 1D-9 Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      A58-37 (IGSW) or 1D-9 - Body ground Always 10 kΩ or higher
      Result
      Result Proceed to
      Outside normal range A
      Within normal range (w/ Entry and Start System) B
      Within normal range (w/o Entry and Start System) C

    4. Reinstall the No. 1 integration relay.

    5. Reconnect the ECM connector.


    A

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    C

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

    B

  7. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - SMART KEY ECU ASSEMBLY)


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

    2. Disconnect the smart key ECU 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
      1D-17- F65-9 (IG2D) Always Below 1 Ω
      1E-10 - Body ground Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      F65-9 (IG2D) or 1D-17 - Body ground Always 10 kΩ or higher

    4. Reinstall the No. 1 integration relay.

    5. Reconnect the smart key ECU assembly connector.


    OK

    REPAIR OR REPLACE ENTRY AND START SYSTEM

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

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


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

    2. Disconnect the ignition switch connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      1D-17 - F13-6 (IG2) Always Below 1 Ω
      1E-10 - Body ground Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      F13-6 (IG2) or 1D-17 - Body ground Always 10 kΩ or higher

    4. Reinstall the No. 1 integration relay.

    5. Reconnect the ignition switch connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  9. INSPECT IGNITION SWITCH


    1. Inspect the ignition switch Click here.


    OK

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

    NG

    REPLACE IGNITION SWITCH Click here