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

  1. CHECK NO. 1 INTEGRATION RELAY (POWER SOURCE) 
    1. Remove the No. 1 integration relay from the No. 1 engine room relay block and junction block assembly.
      GTY522869Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      1D-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:  NG

    NG 

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

    Result:  OK

    OK 

    See step  2

  2. INSPECT NO. 1 INTEGRATION RELAY (EFI MAIN1 RELAY, IG2 RELAY) 
    1. Inspect the No. 1 integration relay (See service information). Refer to PROCEDURE - Step 1 ).

    Result:  NG

    NG 

    REPLACE NO. 1 INTEGRATION RELAY 

    Result:  OK

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (EFI MAIN1 RELAY - ECM, BODY GROUND) 
    1. Remove the No. 1 integration relay from the No. 1 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
      1F-9 - A20-2 (+B) Always Below 1 Ω
      1F-10 - A20-3 (+B2) Always Below 1 Ω
      1E-6 - A20-46 (MREL) Always Below 1 Ω
      1F-6 - A20-32 (IGSW) Always Below 1 Ω
      1F-1 - Body ground Always Below 1 Ω
      1F-9 or A20-2 (+B) - Body ground Always 10 kΩ or higher
      1F-10 or A20-3 (+B2) - Body ground Always 10 kΩ or higher
      1E-6 or A20-46 (MREL) - Body ground Always 10 kΩ or higher
      1F-6 or A20-32 (IGSW) - Body ground Always 10 kΩ or higher
    4. Reinstall the No. 1 integration relay.
    5. Reconnect the ECM connector.

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  4

  4. 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
      F5-49 (E1) - Body ground Always Below 1 Ω
    3. Reconnect the ECM connector.

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  5

  5. INSPECT ECM (IGSW VOLTAGE) 
    1. Disconnect the ECM connector.
      GTY527443Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the power switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A20-32 (IGSW) - Body ground Power switch on (IG) 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to ECM)
    4. Reconnect the ECM connector.

    Result:  OK

    OK 

    REPLACE ECM 

    (See service information). Refer to REMOVAL [09/2014 - ] )

    Result:  NG

    NG 

    GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START 

    (See service information). Refer to Power Source Mode does not Change to ON (IG) [09/2014 - 10/2015] Refer to Power Source Mode does not Change to ON (IG) [10/2015 - ] )

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