СИСТЕМА SFI ECM Power Source Circuit

DESCRIPTION

When the engine switch is turned on (IG), 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 coil of the No. 1 integration relay (EFI relay), closing the contacts and supplying power to terminals +B and +B2 of the ECM.

WIRING DIAGRAM

A01EOUIE02

INSPECTION PROCEDURE

Note

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

PROCEDURE


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

    A01EN9HE02
    Text in Illustration
    *1 No. 1 Integration relay
    *a

    Front view of wire harness connector

    (to No. 1 Integration Relay)


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

    NG
    OK
  2. INSPECT NO. 1 INTEGRATION RELAY (EFI)


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


    NG
    OK
  3. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - ECM, BODY GROUND)


    1. Check the harness and connectors between the No. 1 integration relay and ECM.


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

      2. Disconnect the ECM connector.

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        A53-34 (MREL) - 1B-2 Always Below 1 Ω
        A53-3 (+B) - 1B-4 Always Below 1 Ω
        A53-2 (+B2) - 1B-4 Always Below 1 Ω
        A53-34 (MREL) or 1B-2 - Body ground Always 10 kΩ or higher
        A53-3 (+B) or 1B-4 - Body ground Always 10 kΩ or higher
        A53-2 (+B2) or 1B-4 - Body ground Always 10 kΩ or higher
    2. Check the harness and connectors between the No. 1 integration relay and body ground.


      1. 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

    NG
    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
      Tester Connection Condition Specified Condition
      C54-81 (E1) - Body ground Always Below 1 Ω

    NG
    OK
  5. INSPECT ECM (IGSW VOLTAGE)

    A01ESCVE17
    Text in Illustration
    *a

    Front view of wire harness connector

    (to ECM)


    1. Disconnect the ECM connectors.

    2. Turn the engine switch on (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A53-28 (IGSW) - C54-81 (E1) Engine switch on (IG) 11 to 14 V

    NG
    OK
  6. INSPECT NO. 1 INTEGRATION RELAY (IG2)


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


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


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

    2. Disconnect the ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1B-8 - A53-28 (IGSW) Always Below 1 Ω
      1B-8 or A53-28 (IGSW) - Body ground Always 10 kΩ or higher
      Result
      Result Proceed to
      Out of normal range A
      Within normal range B

    B
    A
  8. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - MAIN BODY ECU, BODY GROUND)


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

    2. Disconnect the main body ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1B-6 - E2-11 (IG2D) Always Below 1 Ω
      1B-7 - Body ground Always Below 1 Ω
      1B-6 or E2-11 (IG2D) - Body ground Always 10 kΩ or higher

    NG
    OK