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ECM Power Source Circuit [09/2013 - ]: Procedure

  1. INSPECT ECM (+B, +B2 VOLTAGE) 
    1. Turn the engine switch on (IG).
      GTY284587Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage

      Tester Connection Switch Condition Specified Condition
      A13-2 (+B) - E3-1 (E1) Engine switch on (IG) 11 to 14 V
      A13-1 (+B2) - E3-1 (E1) Engine switch on (IG) 11 to 14 V

    OK → See step   10 

    NG: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the E3 ECM connector.
      GTY288234Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open)

      Tester Connection Condition Specified Condition
      E3-1 (E1) - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. INSPECT ECM (IGSW VOLTAGE) 
    1. Turn the engine switch on (IG).
      GTY267342Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage

      Tester Connection Switch Condition Specified Condition
      A14-8 (IGSW) - E3-1 (E1) Engine switch on (IG) 11 to 14 V

    OK → See step   6 

    NG: Go to next step 

  4. CHECK FUSE (ECU-IG) 
    1. Remove the ECU-IG fuse from the engine room No. 2 junction block.
      GTY144129Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      ECU-IG Always Below 1 Ω

    NG → CHECK FOR SHORT IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

    OK: Go to next step 

  5. INSPECT IGNITION RELAY NO. 2 (IG2) 
    1. Remove the IG2 relay from the engine room No. 2 junction block.
      GTY260308Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      3 - 5 When no battery voltage applied to terminals 1 and 2 10 kΩ or higher
      3 - 5 When battery voltage applied to terminals 1 and 2 Below 1 Ω

    NG → REPLACE IGNITION RELAY NO. 2 (IG2) 

    OK → See step   11 

  6. INSPECT ECM (MREL VOLTAGE) 
    1. Turn the engine switch on (IG).
      GTY288009Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage

      Tester Connection Switch Condition Specified Condition
      A14-3 (MREL) - E3-1 (E1) Engine switch on (IG) 11 to 14 V

    NG → See step   12 

    OK: Go to next step 

  7. CHECK FUSE (EFI MAIN2) 
    1. Remove the EFI MAIN2 fuse from the engine room No. 2 relay block.
      GTY147589Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      EFI MAIN2 Always Below 1 Ω

    NG → CHECK FOR SHORT IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

    OK: Go to next step 

  8. INSPECT EFI RELAY (EFI MAIN2) 
    1. Remove the EFI MAIN2 relay from the engine room No. 2 relay block.
      GTY102844Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      3 - 5 When no battery voltage applied to terminals 1 and 2 10 kΩ or higher
      When battery voltage applied to terminals 1 and 2 Below 1 Ω

    NG → REPLACE EFI RELAY (EFI MAIN2) 

    OK: Go to next step 

  9. CHECK HARNESS AND CONNECTOR (EFI RELAY (EFI MAIN2) - ECM, BODY GROUND) 
    GTY288279Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Check the harness and the connectors between the integration relay and the ECM.
      1. Remove the EFI MAIN2 relay from the engine room No. 2 relay block.
      2. Disconnect the A14 ECM connector.
      3. Measure the resistance according to the value(s) in the table below.

        Standard resistance (Check for open)

        Tester Connection Condition Specified Condition
        EFI MAIN2 relay (1) - A14-3 (MREL) Always Below 1 Ω

        Standard resistance (Check for short)

        Tester Connection Condition Specified Condition
        EFI MAIN2 relay (1) or A14-3 (MREL) - Body ground Always 10 kΩ or higher
    2. Check the harness and the connectors between the EFI MAIN2 relay and body ground.
      1. Remove the EFI MAIN2 relay from the engine room No. 2 relay block.
      2. Measure the resistance according to the value(s) in the table below.

        Standard resistance (Check for open)

        Tester Connection Condition Specified condition
        EFI MAIN2 relay (2) - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → CHECK AND REPAIR HARNESS OR CONNECTOR (TERMINAL +B OF ECM - BATTERY POSITIVE TERMINAL) 

  10. PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [09/2013 - ] 
  11. GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START. Refer to  Power Source Mode does not Change [09/2013 - ] 
  12. REPLACE ECM. Refer to  REMOVAL [09/2013 - ] 
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