SFI SYSTEM ECM Power Source Circuit

DESCRIPTION

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

WIRING DIAGRAM



CAUTION / NOTICE / HINT

Note

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

PROCEDURE


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

    B001HXIE04
    Text in Illustration
    *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 and junction block assembly.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      1S-1 - Body ground Always 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


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

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


    NG

    REPLACE NO. 1 INTEGRATION RELAY

    OK

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


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

    2. Disconnect the ECM connector.

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

      Standard Resistance (Check for Open)
      for Automatic Transmission
      Tester Connection Condition Specified Condition
      G56-36 (MREL) - 1W-8 Always Below 1 Ω
      G55-23 (+B) - 1W-10 Always Below 1 Ω
      G55-22 (+B2) - 1W-10 Always Below 1 Ω
      for Manual Transmission
      Tester Connection Condition Specified Condition
      G55-9 (MREL) - 1W-8 Always Below 1 Ω
      G55-22 (+B) - 1W-10 Always Below 1 Ω
      G55-23 (+B2) - 1W-10 Always Below 1 Ω
      Standard Resistance (Check for Short)
      for Automatic Transmission
      Tester Connection Condition Specified Condition
      G56-36 (MREL) or 1W-8 - Body ground and other terminals Always 10 kΩ or higher
      G55-23 (+B) or 1W-10 - Body ground and other terminals Always 10 kΩ or higher
      G55-22 (+B2) or 1W-10 - Body ground and other terminals Always 10 kΩ or higher
      for Manual Transmission
      Tester Connection Condition Specified Condition
      G55-9 (MREL) or 1W-8 - Body ground and other terminals Always 10 kΩ or higher
      G55-22 (+B) or 1W-10 - Body ground and other terminals Always 10 kΩ or higher
      G55-23 (+B2) or 1W-10 - Body ground and other terminals Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1W-4 - Body ground Always Below 1 Ω

    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 (Check for Open)
      Tester Connection Condition Specified Condition
      C36-12 (E1) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. INSPECT ECM (IGSW VOLTAGE)

    B001E0AE02
    Text in Illustration
    *A for Automatic Transmission
    *B for Manual Transmission
    *a

    Component with harness connected

    (ECM)

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

      Standard Voltage
      for Automatic Transmission
      Tester Connection Switch Condition Specified Condition
      G55-21 (IGSW) - C36-12 (E1) Engine switch on (IG) 11 to 14 V
      for Manual Transmission
      Tester Connection Switch Condition Specified Condition
      G56-21 (IGSW) - C36-12 (E1) Engine switch on (IG) 11 to 14 V

    OK

    REPLACE ECM Click here

    NG

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


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

    2. Disconnect the ECM connector.

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

      Standard Resistance (Check for Open)
      for Automatic Transmission
      Tester Connection Condition Specified Condition
      1V-1 - G55-21 (IGSW) Always Below 1 Ω
      for Manual Transmission
      Tester Connection Condition Specified Condition
      1V-1 - G56-21 (IGSW) Always Below 1 Ω
      Standard Resistance (Check for Short)
      for Automatic Transmission
      Tester Connection Condition Specified Condition
      1V-1 or G52-21 (IGSW) - Body ground and other terminals Always 10 kΩ or higher
      for Manual Transmission
      Tester Connection Condition Specified Condition
      1V-1 or G56-21 (IGSW) - Body ground and other terminals Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


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

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

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      G213-3 (IG1D) - 1V-2 Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      G213-3 (IG1D) or 1V-2 - Body ground and other terminals Always 10 kΩ or higher

    OK

    GO TO ENTRY AND START SYSTEM Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR