SFI SYSTEM(w/o Canister Pump Module) 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 No. 1 integration relay (EFI-MAIN relay), closing the contacts of the EFI-MAIN relay and supplying power to terminals +B and +B2 of the ECM.

WIRING DIAGRAM

B004PY6E01

CAUTION / NOTICE / HINT

Note

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

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (POWER SOURCE OF NO. 1 INTEGRATION RELAY)


    1. Disconnect the No. 1 integration relay connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      1A-10 - Body ground Always 11 to 14 V
      1B-3 - Body ground Always 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

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

    OK

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


    1. Inspect the No. 1 integration relay (EFI-MAIN relay, IG2 NO. 1 relay).

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE NO. 1 INTEGRATION RELAY Click here

    OK

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


    1. Disconnect the No. 1 integration relay connector.

    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
      1A-9 - A40-6 (IGSW) Always Below 1 Ω
      1B-6 - A40-46 (MREL) Always Below 1 Ω
      1B-4 - A40-2 (+B) Always Below 1 Ω
      1B-4 - A40-3 (+B2) Always Below 1 Ω
      1A-9 or A40-6 (IGSW) - Body ground and other terminals Always 10 kΩ or higher
      1B-6 or A40-46 (MREL) - Body ground and other terminals Always 10 kΩ or higher
      1B-4 or A40-2 (+B) - Body ground and other terminals Always 10 kΩ or higher
      1B-4 or A40-3 (+B2) - Body ground and other terminals Always 10 kΩ or higher

      Tech Tips

      If a short is detected in any of the above circuits, there may be a malfunction in the circuit of a connected ECU.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - BODY GROUND)


    1. Disconnect the No. 1 integration relay connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1A-8 - Body ground Always Below 1 Ω
      1B-5 - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. 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
      C31-59 (E1) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. INSPECT ECM (IGSW VOLTAGE)


    1. 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
      A40-6 (IGSW) - Body ground Power switch on (IG) 11 to 14 V
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

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


    1. Disconnect the certification ECU (smart key ECU assembly) connector.

    2. Disconnect the No. 1 integration relay connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F1-17 (IG1D) - 1A-7 Always Below 1 Ω
      F1-17 (IG1D) or 1A-7 - Body ground and other terminals Always 10 kΩ or higher

      Tech Tips

      If a short is detected in any of the above circuits, there may be a malfunction in the circuit of a connected ECU.

      Result
      Proceed to
      OK
      NG

    OK

    GO TO ENTRY AND START SYSTEM (FOR START FUNCTION) Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR