SFI SYSTEM ECM Power Source Circuit

DESCRIPTION

When the power switch is turned on (IG), auxiliary battery voltage is applied to the IGSW terminal of the ECM. The output signal from the MREL terminal of the ECM causes current to flow to the coil of the integration relay (EFI-MAIN relay), closing the contact and supplying power to terminals +B and +B2 of the ECM.

WIRING DIAGRAM

A00YPL0E02

CAUTION / NOTICE / HINT

Note


  • After turning power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

  • Inspect the fuses for circuits related to this system before performing the following 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
      B178-16 (E1) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. CHECK TERMINAL VOLTAGE (IGSW VOLTAGE)


    1. A00YOJEC35
      *a Front view of wire harness or connector (to ECM)

      Disconnect the ECM connector.

    2. Turn the power switch on (IG).

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A142-37 (IGSW) - Body ground Power switch on (IG) 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    INSPECT INTEGRATION RELAY (IG2 RELAY) Click here

    OK

  3. INSPECT INTEGRATION RELAY (EFI-MAIN RELAY)


    1. Inspect the integration relay (EFI-MAIN relay).

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE INTEGRATION RELAY (EFI-MAIN REALY) Click here

    OK

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


    1. Disconnect the ECM connector.

    2. Remove the integration relay (EFI-MAIN relay) from the No. 1 engine room relay block and No. 1 junction block assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A142-46 (MREL) - 1J-2 Always Below 1 Ω
      A142-2 (+B) - 1J-4 Always Below 1 Ω
      A142-3 (+B2) - 1J-4 Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (INTEGRATION REALY (EFI-MAIN RELAY) - BODY GROUND)


    1. Remove the integration relay (EFI-MAIN relay) from the No. 1 engine room relay block and No. 1 junction block assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1J-3 - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  6. INSPECT INTEGRATION RELAY (IG2 RELAY)


    1. Inspect the integration relay (IG2 relay).

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE INTEGRATION RELAY (IG2 REALY) Click here

    OK

  7. CHECK HARNESS AND CONNECTOR (ECM - INTEGRATION RELAY (IG2 RELAY))


    1. Disconnect the ECM connector.

    2. Remove the integration relay (IG2 relay) from the No. 1 engine room relay block and No. 1 junction block assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A142-37 (IGSW) - 1K-4 Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY (IG2 RELAY) - AUXILIARY BATTERY)


    1. Remove the integration relay (IG2 relay) from the No. 1 engine room relay block and No. 1 junction block assembly.

    2. Disconnect the negative (-) auxiliary battery terminal.

    3. Disconnect the positive (+) auxiliary battery terminal.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1L-1 - Positive (+) auxiliary battery terminal Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  9. CHECK HARNESS AND CONNECTOR (INTEGRATION REALY (IG2 RELAY) - BODY GROUND)


    1. Remove the integration relay (IG2 relay) from the No. 1 engine room relay block and No. 1 junction block assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1K-3 - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  10. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - INTEGRATION RELAY (IG2 RELAY))


    1. Disconnect the power management control ECU connector.

    2. Remove the integration relay (IG2 relay) from the No. 1 engine room relay block and No. 1 junction block assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A130-2 (IG2D) - 1K-2 Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    GO TO ENTRY AND START SYSTEM Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR