SFI SYSTEM ECM Power Source Circuit

DESCRIPTION

When the ignition switch is turned to ON, 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 and supplying power to terminals +B and +B2 of the ECM.

WIRING DIAGRAM

A011RYKE03

INSPECTION PROCEDURE

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 VOLTAGE)

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

    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
      1C-8 - Body ground Ignition switch ON 11 to 14 V
      Result
      Result Proceed to
      OK A
      NG (w/o smart key system) B
      NG (w/ smart key system) C
    B

    CHECK HARNESS AND CONNECTOR (BATTERY - IGNITION SWITCH ASSEMBLY) Click here

    C

    CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - NO. 1 INTEGRATION RELAY) Click here

    A

  2. CHECK HARNESS AND CONNECTOR (BATTERY - 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
      1D-3 - Body ground Always 11 to 14 V
      1B-1 - Body ground Always 11 to 14 V
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT NO. 1 INTEGRATION RELAY

    1. Inspect the No. 1 integration relay Click here.

    NG

    REPLACE NO. 1 INTEGRATION RELAY Click here

    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
      1E-2 - Body ground Always Below 1 Ω
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. 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
      Tester Connection Condition Specified Condition
      1C-1- A25-37 (IGSW) Always Below 1 Ω
      1C-9 - A25-2 (+B) Always Below 1 Ω
      1C-10 - A25-3 (+B2) Always Below 1 Ω
      1C-7 - A25-46 (MREL) Always Below 1 Ω
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. 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
      E26-16 (E1) - Body ground Always Below 1 Ω
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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

  7. CHECK HARNESS AND CONNECTOR (BATTERY - IGNITION SWITCH ASSEMBLY)

    1. Disconnect the ignition switch assembly connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      I36-5 (AM2) - Body ground Always 11 to 14 V
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. 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 (NO. 1 INTEGRATION RELAY - IGNITION SWITCH ASSEMBLY)

  9. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - 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
      Tester Connection Condition Specified Condition
      A43-9 (IG2D) - 1C-8 Always Below 1 Ω
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    GO TO SMART KEY SYSTEM Click here