SFI SYSTEM (w/ EGR System) ECM Power Source Circuit

DESCRIPTION

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

WIRING DIAGRAM

A01J9Y1E01

INSPECTION PROCEDURE

Note

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

PROCEDURE


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


    1. A01JBYBE52
      Text in Illustration
      *1

      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
      D28-104 (E1) - Body ground Always Below 1 Ω

    3. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - BODY GROUND)

    OK

  2. INSPECT ECM (IGSW VOLTAGE)


    1. A01J9BKE25
      Text in Illustration
      *1

      Front view of wire harness 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 Switch Condition Specified Condition
      A57-28 (IGSW) - Body ground Power switch on (IG) 11 to 14 V

    4. Reconnect the ECM connector.


    NG

    INSPECT INTEGRATION RELAY (IG2 RELAY) Click here

    OK

  3. INSPECT INTEGRATION RELAY (EFI MAIN RELAY)


    1. A01JBZNE06
      Text in Illustration
      *1

      Component without harness connected

      (Integration Relay)

      Remove the integration relay from the engine room relay block.

    2. Disconnect the integration relay connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1C-1 - 1B-4 No battery voltage applied between terminals 1B-2 and 1B-3 10 kΩ or higher
      Battery voltage applied between terminals 1B-2 and 1B-3 Below 1 Ω

    4. Reconnect the integration relay connector.

    5. Reinstall the integration relay.


    NG

    REPLACE INTEGRATION RELAY Click here

    OK

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


    1. Remove the integration relay from the engine room relay block.

      A01JANWE01

    2. Disconnect the integration relay connector.

    3. Disconnect the ECM connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      1B-4 - A57-1 (+B2) Always Below 1 Ω
      1B-4 - A57-2 (+B) Always Below 1 Ω
      1B-2 - A57-6 (MREL) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      1B-4 or A57-1 (+B2) - Body ground Always 10 kΩ or higher
      1B-4 or A57-2 (+B) - Body ground Always 10 kΩ or higher
      1B-2 or A57-6 (MREL) - Body ground Always 10 kΩ or higher
      Text in Illustration
      *1

      Front view of wire harness connector

      (to ECM)

      		 *2 Integration Relay
      *3

      Front view of wire harness connector

      (to Integration Relay)

      		 - -

    5. Reconnect the ECM connector.

    6. Reconnect the integration relay connector.

    7. Reinstall the integration relay.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY (EFI MAIN RELAY) - ECM)

    OK

  5. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY (EFI MAIN RELAY) - BATTERY)


    1. A01J98KE01
      Text in Illustration
      *1 Integration Relay
      *2

      Front view of wire harness connector

      (to Integration Relay)

      Remove the integration relay from the engine room relay block.

    2. Disconnect the integration relay connector.

    3. Disconnect the negative battery terminal.

    4. Disconnect the positive battery terminal.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      1C-1 - Battery positive terminal Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      1C-1 or Battery positive terminal - Body ground Always 10 kΩ or higher

    6. Reconnect the integration relay connector.

    7. Reinstall the integration relay.

    8. Reconnect the positive battery terminal.

    9. Reconnect the negative battery terminal.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY (EFI MAIN RELAY) - BATTERY)

    OK

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


    1. A01JA5ZE01
      Text in Illustration
      *1 Integration Relay
      *2

      Front view of wire harness connector

      (to Integration Relay)

      Remove the integration relay from the engine room relay block.

    2. Disconnect the integration relay connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1B-3 - Body ground Always Below 1 Ω

    4. Reconnect the integration relay connector.

    5. Reinstall the integration relay.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY (EFI MAIN RELAY) - BODY GROUND)

    OK

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

  7. INSPECT INTEGRATION RELAY (IG2 RELAY)


    1. A01JBZNE07
      Text in Illustration
      *1

      Component without harness connected

      (Integration Relay)

      Remove the integration relay from the engine room relay block.

    2. Disconnect the integration relay connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1C-1 - 1A-4 No battery voltage applied to terminals 1A-2 and 1A-3 10 kΩ or higher
      Battery voltage applied to terminals 1A-2 and 1A-3 Below 1 Ω

    4. Reconnect the integration relay connector.

    5. Reinstall the integration relay.


    NG

    REPLACE INTEGRATION RELAY (IG2 RELAY) Click here

    OK

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


    1. Disconnect the ECM connector.

      A01JCOYE01

    2. Remove the integration relay from the engine room relay block.

    3. Disconnect the integration relay connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      1A-4 - A57-28 (IGSW) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      1A-4 or A57-28 (IGSW) - Body ground Always 10 kΩ or higher
      Text in Illustration
      *1

      Front view of wire harness connector

      (to ECM)

      		 *2 Integration Relay
      *3

      Front view of wire harness connector

      (to Integration Relay)

      		 - -

    5. Reconnect the ECM connector.

    6. Reconnect the integration relay connector.

    7. Reinstall the integration relay.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY (IG2 RELAY) - ECM)

    OK

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


    1. A01J98KE01
      Text in Illustration
      *1 Integration Relay
      *2

      Front view of wire harness connector

      (to Integration Relay)

      Remove the integration relay from the engine room relay block.

    2. Disconnect the integration relay connector.

    3. Disconnect the negative battery terminal.

    4. Disconnect the positive battery terminal.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      1C-1 - Battery positive terminal Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      1C-1 or Battery positive terminal - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY (IG2 RELAY) - BATTERY)

    OK

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


    1. A01JD4CE01
      Text in Illustration
      *1 Integration Relay
      *2

      Front view of wire harness connector

      (to Integration Relay)

      Remove the integration relay from the engine room relay block.

    2. Disconnect the integration relay connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1A-3 - Body ground Always Below 1 Ω

    4. Reconnect the integration relay connector.

    5. Reinstall the integration relay.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY (IG2 RELAY) - BODY GROUND)

    OK

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


    1. Remove the integration relay from the engine room relay block.

      A01JBULE01

    2. Disconnect the integration relay connector.

    3. Disconnect the power management control ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A22-2 (IG2D) - 1A-2 Always Below 1 Ω
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Power Management Control ECU)

      		 *2 Integration Relay
      *3

      Front view of wire harness connector

      (to Integration Relay)

      		 - -

    5. Reconnect the integration relay connector.

    6. Reinstall the integration relay.

    7. Reconnect the power management control ECU connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER MANAGEMENT CONTROL ECU - INTEGRATION RELAY (IG2 RELAY))

    OK

    CHECK ENTRY AND START SYSTEM Click here