SFI SYSTEM ECM Power Source Circuit

DESCRIPTION

When the ignition switch is turned to ON, the 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 or +B2 of the ECM.

WIRING DIAGRAM

A01IQKLE02

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. A01IS43E79
      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
      C68-105 (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. A01IRICE09
      Text in Illustration
      *1

      Front view of wire harness connector

      (to ECM)

      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
      A51-27 (IGSW) - Body ground Ignition switch ON 11 to 14 V

    4. Reconnect the ECM connector.


    NG

    INSPECT INTEGRATION RELAY (IG2) Click here

    OK

  3. INSPECT INTEGRATION RELAY (EFI MAIN)


    1. A01IPBCE01
      Text in Illustration
      *1 Engine Room No. 1 Relay Block
      *2

      Component without harness connected

      (Integration Relay)

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

    2. Disconnect the integration relay connector.

    3. Measure the EFI MAIN relay resistance.

      Standard Resistance
      Tester Connection Condition Specified Condition
      1C-1 - 1B-4 Battery voltage is not applied to terminals 1B-2 and 1B-3 10 kΩ or higher
      Battery voltage is applied to 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) - ECM)


    1. A01IOK2E03
      Text in Illustration
      *1 Engine Room No. 1 Relay Block
      *2

      Front view of wire harness connector

      (to Integration Relay)
      *3

      Front view of wire harness connector

      (to ECM)

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

    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 - A51-2 (+B) Always Below 1 Ω
      1B-4 - A51-1 (+B2) Always Below 1 Ω
      Standard Resistance (Check for short)
      Tester Connection Condition Specified Condition
      1B-4 or A51-2 (+B) - Body ground Always 10 kΩ or higher
      1B-4 or A51-1 (+B2) - Body ground Always 10 kΩ or higher

    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) - ECM)

    OK

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


    1. Disconnect the negative battery terminal.

    2. Disconnect the positive battery terminal.

    3. A01ISJME01
      Text in Illustration
      *1 Engine Room No. 1 Relay Block
      *2

      Front view of wire harness connector

      (to Integration Relay)

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

    4. Disconnect the integration relay connector.

    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 (EFI MAIN RELAY - BATTERY)

    OK

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


    1. A01ISE2E01
      Text in Illustration
      *1 Engine Room No. 1 Relay Block
      *2

      Front view of wire harness connector

      (to Integration Relay)

      Remove the integration relay from the engine room No. 1 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) - BODY GROUND)

    OK

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


    1. A01IOK2E04
      Text in Illustration
      *1 Engine Room No. 1 Relay Block
      *2

      Front view of wire harness connector

      (to Integration Relay)
      *3

      Front view of wire harness connector

      (to ECM)

      Disconnect the ECM connector.

    2. Remove the integration relay from the engine room No. 1 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
      1B-2 - A51-44 (MREL) Always Below 1 Ω
      Standard Resistance (Check for short)
      Tester Connection Condition Specified Condition
      1B-2 or A51-44 (MREL) - Body ground Always 10 kΩ or higher

    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) - ECM)

    OK

    REPLACE ECM Click here

  8. INSPECT INTEGRATION RELAY (IG2)


    1. A01IPBCE01
      Text in Illustration
      *1 Engine Room No. 1 Relay Block
      *2

      Component without harness connected

      (Integration Relay)

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

    2. Disconnect the integration relay connector.

    3. Measure the IG2 relay resistance.

      Standard Resistance
      Tester Connection Condition Specified Condition
      1C-1 - 1A-4 Battery voltage is not applied to terminals 1A-2 and 1A-3 10 kΩ or higher
      Battery voltage is not 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 Click here

    OK

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


    1. A01ITOVE02
      Text in Illustration
      *1 Engine Room No. 1 Relay Block
      *2

      Front view of wire harness connector

      (to Integration Relay)
      *3

      Front view of wire harness connector

      (to ECM)

      Disconnect the ECM connector.

    2. Remove the integration relay from the engine room No. 1 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 - A51-27 (IGSW) Always Below 1 Ω
      Standard Resistance (Check for short)
      Tester Connection Condition Specified Condition
      1A-4 or A51-27 (IGSW) - Body ground Always 10 kΩ or higher

    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) - ECM)

    OK

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


    1. Disconnect the negative battery terminal.

    2. Disconnect the positive battery terminal.

    3. A01ISJME01
      Text in Illustration
      *1 Engine Room No. 1 Relay Block
      *2

      Front view of wire harness connector

      (to Integration Relay)

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

    4. Disconnect the integration relay connector.

    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 (IG2) - BATTERY)

    OK

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


    1. A01IQKSE01
      Text in Illustration
      *1 Engine Room No. 1 Relay Block
      *2

      Front view of wire harness connector

      (to Integration Relay)

      Remove the integration relay from the engine room No. 1 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-2 - 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) - BODY GROUND)

    OK

  12. CHECK IF VEHICLE IS EQUIPPED WITH ENTRY AND START SYSTEM


    1. Confirm the entry and start system.

      Result
      Result Proceed to
      w/o Entry and Start System A
      w/ Entry and Start System B

    B

    CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - POWER MANAGEMENT CONTROL ECU) Click here

    A

  13. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY (IG2) - IGNITION SWITCH)


    1. A01IOXXE02
      Text in Illustration
      *1 Engine Room No. 1 Relay Block
      *2

      Front view of wire harness connector

      (to Integration Relay)
      *3

      Front view of wire harness connector

      (to Ignition Switch)

      Disconnect the ignition switch connector.

    2. Remove the integration relay from the engine room No. 1 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-3 - H6-6 (IG2) Always Below 1 Ω
      Standard Resistance (Check for short)
      Tester Connection Condition Specified Condition
      1A-3 or H6-6 (IG2) - Body ground Always 10 kΩ or higher

    5. Reconnect the ignition switch connector.

    6. Reconnect the integration relay connector.

    7. Reinstall the integration relay.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY (IG2) - IGNITION SWITCH)

    OK

  14. 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 - BATTERY)

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


    1. A01IT3PE02
      Text in Illustration
      *1 Engine Room No. 1 Relay Block
      *2

      Front view of wire harness connector

      (to Integration Relay)
      *3

      Rear view of wire harness connector

      (to Power Management Control ECU)

      Disconnect the power management control ECU connector.

    2. Remove the integration relay from the engine room No. 1 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-3 - H70-8 (IG2D) Always Below 1 Ω
      Standard Resistance (Check for short)
      Tester Connection Condition Specified Condition
      1A-3 or H70-8 (IG2D) - Body ground Always 10 kΩ or higher

    5. Reconnect the power management control ECU connector.

    6. Reconnect the integration relay connector.

    7. Reinstall the integration relay.


    NG

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

    OK

    CHECK ENTRY AND START SYSTEM Click here