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ECM Power Source Circuit [09/2014 - 10/2015]: Procedure

  1. INSPECT ECM (+B, +B2 VOLTAGE) 
    1. Turn the engine switch on (IG).
      GTY669242Courtesy 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
      A21-2 (+B) - F4-1 (E1) Engine switch on (IG) 11 to 14 V
      A21-1 (+B2) - F4-1 (E1) Engine switch on (IG) 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (ECM)

    Result: 

    OK 

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE 

    (Refer to PROBLEM SYMPTOMS TABLE [09/2014 - 10/2015] )

    Result: 

    NG 

    See step  2

  2. 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
      F4-1 (E1) - Body ground Always Below 1 Ω
    3. Reconnect the ECM connector.

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - BODY GROUND) 

    Result: 

    OK 

    See step  3

  3. INSPECT ECM (IGSW VOLTAGE) 
    1. Turn the engine switch on (IG).
      GTY664611Courtesy 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
      A19-8 (IGSW) - F4-1 (E1) Engine switch on (IG) 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (ECM)

    Result: 

    NG 

    See step  8

    Result: 

    OK 

    See step  4

  4. INSPECT ECM (MREL VOLTAGE) 
    1. Turn the engine switch on (IG).
      GTY626587Courtesy 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
      A19-3 (MREL) - F4-1 (E1) Engine switch on (IG) 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (ECM)

    Result: 

    NG 

    REPLACE ECM 

    (Refer to REMOVAL [09/2014 - 10/2015] )

    Result: 

    OK 

    See step  5

  5. INSPECT NO. 1 INTEGRATION RELAY (EFI MAIN1 RELAY) 
    1. Inspect the No. 1 integration relay (Refer to PROCEDURE - Step 1 ).

    Result: 

    NG 

    REPLACE NO. 1 INTEGRATION RELAY 

    Result: 

    OK 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (EFI MAIN1 RELAY - ECM) 
    1. Remove the No. 1 integration relay from the No. 2 engine room relay block.
    2. Disconnect the 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
      2E-6 - A19-3 (MREL) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      2E-6 or A19-3 (MREL) - Body ground Always 10 kΩ or higher
    4. Reconnect the ECM connector.
    5. Reinstall the No. 1 integration relay.

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI MAIN1 RELAY - ECM) 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (EFI MAIN1 RELAY - ECM) 
    1. Remove the No. 1 integration relay from the No. 2 engine room relay block.
    2. Disconnect the 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
      2F-9 - A21-2 (+B) Always Below 1 Ω
      2F-10 - A21-1 (+B2) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      2F-9 or A21-2 (+B) - Body ground Always 10 kΩ or higher
      2F-10 or A21-1 (+B2) - Body ground Always 10 kΩ or higher
    4. Reinstall the No. 1 integration relay.
    5. Reconnect the ECM connector.

    Result: 

    OK 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - NO. 1 INTEGRATION RELAY) 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI MAIN1 RELAY - ECM) 

  8. INSPECT NO. 1 INTEGRATION RELAY (IG2 RELAY) 
    1. Inspect the No. 1 integration relay (Refer to PROCEDURE - Step 4 ).

    Result: 

    NG 

    REPLACE NO. 1 INTEGRATION RELAY 

    Result: 

    OK 

    See step  9

  9. CHECK HARNESS AND CONNECTOR (ECM - IG2 RELAY, BODY GROUND) 
    1. Check the harness and the connectors between the No. 1 integration relay and the ECM.
      1. Remove the No. 1 integration relay from the No. 2 engine room relay block.
      2. Disconnect the 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
        2F-6 - A19-8 (IGSW) Always Below 1 Ω

        Standard Resistance (Check for Short)

        Tester Connection Condition Specified Condition
        2F-6 or A19-8 (IGSW) - Body ground Always 10 kΩ or higher
      4. Reconnect the ECM connector.
    2. Check the harness and the connectors between the No. 1 integration relay and body ground.
      1. Measure the resistance according to the value(s) in the table below.

        Standard Resistance (Check for Open)

        Tester Connection Condition Specified Condition
        2F-1 - Body ground Always Below 1 Ω
      2. Reinstall the No. 1 integration relay.

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - IG2 RELAY, BODY GROUND) 

    Result: 

    OK 

    See step  10

  10. CHECK NO. 1 INTEGRATION RELAY (POWER SOURCE) 
    1. Remove the No. 1 integration relay from the No. 2 engine room relay block.
      GTY633186Courtesy 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
      2D-1 - Body ground Always 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      to No. 1 Integration Relay
    3. Reinstall the No. 1 integration relay.

    Result: 

    OK 

    GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START 

    (Refer to HOW TO PROCEED WITH TROUBLESHOOTING [09/2014 - ] )

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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