ECD SYSTEM(w/o Glow Plug Controller) ECM Power Source Circuit

DTC Code DTC Name
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 a current to flow to the EFI-MAIN relay coil, closing the EFI-MAIN relay contacts and supplying power to terminals +B and +B2 of the ECM.

WIRING DIAGRAM

A294973E01

CAUTION / NOTICE / HINT

Note:

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

PROCEDURE

  1. CHECK TERMINAL VOLTAGE (POWER SOURCE OF IG2 RELAY)

    1. A290380C03

      *1

      Engine Room Relay Block and Junction Block Assembly

      *2

      IG2 Relay

      Remove the IG2 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

      IG2 relay terminal 3 - Body ground

      Always

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - IG2 RELAY)

    OK

  2. CHECK TERMINAL VOLTAGE (POWER SOURCE OF EFI-MAIN RELAY)

    1. A290379C03

      *1

      Engine Room Relay Block and Junction Block Assembly

      *2

      EFI-MAIN Relay

      Remove the EFI-MAIN 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

      EFI-MAIN relay terminal 5 - Body ground

      Always

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - EFI-MAIN RELAY)

    OK

  3. INSPECT RELAY (IG2 RELAY)

    1. Inspect the IG2 relay.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE RELAY (IG2 RELAY)

    OK

  4. INSPECT RELAY (EFI-MAIN RELAY)

    1. Inspect the EFI-MAIN relay.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE RELAY (EFI-MAIN RELAY)

    OK

  5. CHECK HARNESS AND CONNECTOR (IG2 RELAY - BODY GROUND)

    1. Remove the IG2 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

      IG2 relay terminal 2 - Body ground

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK HARNESS AND CONNECTOR (EFI-MAIN RELAY - BODY GROUND)

    1. Remove the EFI-MAIN 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

      EFI-MAIN relay terminal 2 - Body ground

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. CHECK HARNESS AND CONNECTOR (IG2 RELAY - ECM)

    1. Remove the IG2 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

      IG2 relay terminal 5 - A101-7 (IGSW)

      Always

      Below 1 Ω

      IG2 relay terminal 5 or A101-7 (IGSW) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK HARNESS AND CONNECTOR (EFI-MAIN RELAY - ECM)

    1. Remove the EFI-MAIN 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

      EFI-MAIN relay terminal 3 - A101-1 (+B)

      Always

      Below 1 Ω

      EFI-MAIN relay terminal 3 - A101-61 (+B2)

      Always

      Below 1 Ω

      EFI-MAIN relay terminal 1 - A101-22 (MREL)

      Always

      Below 1 Ω

      EFI-MAIN relay terminal 3 or A101-1 (+B) - Body ground

      Always

      10 kΩ or higher

      EFI-MAIN relay terminal 3 or A101-61 (+B2) - Body ground

      Always

      10 kΩ or higher

      EFI-MAIN relay terminal 1 or A101-22 (MREL) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  9. 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

      A101-2 (E1) - Body ground

      Always

      Below 1 Ω

    Result

    Result

    Proceed to

    OK (w/ Entry and Start System)

    A

    OK (w/o Entry and Start System)

    B

    NG

    C
    B

    CHECK HARNESS AND CONNECTOR (IGNITION OR STARTER SWITCH ASSEMBLY - IG2 RELAY)Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    A

  10. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - IG2 RELAY)

    1. Remove the IG2 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

      E33-9 (IG2D) - IG2 relay terminal 1

      Always

      Below 1 Ω

      E33-9 (IG2D) or IG2 relay terminal 1 - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    OK

    GO TO ENTRY AND START SYSTEM

    Click hereClick here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  11. CHECK HARNESS AND CONNECTOR (IGNITION OR STARTER SWITCH ASSEMBLY - IG2 RELAY)

    1. Remove the IG2 relay from the engine room relay block and junction block assembly.

    2. Disconnect the ignition or starter switch assembly connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E4-3 (IG2) - IG2 relay terminal 1

      Always

      Below 1 Ω

      E4-3 (IG2) or IG2 relay terminal 1 - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  12. INSPECT IGNITION OR STARTER SWITCH ASSEMBLY

    1. Inspect the ignition or starter switch assembly.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE IGNITION OR STARTER SWITCH ASSEMBLY

    Click here

    OK

  13. CHECK TERMINAL VOLTAGE (POWER SOURCE OF IGNITION OR STARTER SWITCH ASSEMBLY)

    1. A257670C02

      *a

      Front view of wire harness connector

      (to Ignition or Starter Switch Assembly)

      Disconnect the ignition or starter switch assembly connector.

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      E4-4 (AM2) - Body ground

      Always

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

    Click hereClick here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - IGNITION OR STARTER SWITCH ASSEMBLY)