SFI SYSTEM 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 contact and supplying power to terminals +B and +B2 of the ECM.

WIRING DIAGRAM

A011VJWE02

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. Disconnect the ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E28-16 (E1) - Body ground Always Below 1 Ω
    NG
    OK
  2. CHECK TERMINAL VOLTAGE (IGSW VOLTAGE)

    1. Disconnect the ECM connector.

      A011WD6E14
    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
      A25-37 (IGSW) - Body ground Power switch on (IG) 11 to 14 V
      Text in Illustration
      *a

      Front view of wire harness connector

      (to ECM)

    NG
    OK
  3. INSPECT NO. 1 INTEGRATION RELAY (EFI MAIN RELAY)

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

    NG
    OK
  4. 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-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
      1C-9 or A25-2 (+B) - Body ground Always 10 kΩ or higher
      1C-10 or A25-3 (+B2) - Body ground Always 10 kΩ or higher
      1C-7 or A25-46 (MREL) - Body ground Always 10 kΩ or higher
    NG
    OK
  5. CHECK TERMINAL VOLTAGE (POWER SOURCE OF NO. 1 INTEGRATION RELAY)

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

      A011VUKE01
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      1B-1 - Body ground Always 11 to 14 V
      Text in Illustration
      *a

      Front view of wire harness connector

      (to No. 1 Integration Relay)

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

    1. Inspect the No. 1 integration relay (IG2 relay) 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 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-1 or A25-37 (IGSW) - Body ground Always 10 kΩ or higher
    NG
    OK
  8. CHECK TERMINAL VOLTAGE (POWER SOURCE OF NO. 1 INTEGRATION RELAY)

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

      A011VPBE05
    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
      Text in Illustration
      *a

      Front view of wire harness connector

      (to No. 1 Integration Relay)

    NG
    OK
  9. 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
    OK
  10. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - NO. 1 INTEGRATION RELAY

    1. Disconnect the power management control ECU connector.

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A39-2 (IG2D) - 1C-8 Always Below 1 Ω
      A39-2 (IG2D) or 1C-8 - Body ground Always 10 kΩ or higher
    NG
    OK