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

  1. CHECK HARNESS AND CONNECTOR (IG2-MAIN RELAY VOLTAGE) 
    GTY516972Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 No. 1 Engine Room Relay Block and Junction Block Assembly
    *2 IG2-MAIN Relay
    1. Remove the IG2-MAIN relay from the No. 1 engine room relay block and junction block assembly.
    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
      1 (IG2-MAIN relay) - Body ground Power switch on (IG) 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  11

    Result: 

    OK 

    See step  2

  2. INSPECT IG2-MAIN RELAY 
    1. Inspect the IG2-MAIN relay.

      Refer to PROCEDURE - Step 4

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE IG2-MAIN RELAY 

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (AUXILIARY BATTERY - IG2-MAIN RELAY) 
    GTY516972Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 No. 1 Engine Room Relay Block and Junction Block Assembly
    *2 IG2-MAIN Relay
    1. Remove the IG2-MAIN relay from the No. 1 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
      3 (IG2-MAIN relay) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (IG2-MAIN RELAY - BODY GROUND) 
    1. Remove the IG2-MAIN relay from the No. 1 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
      2 (IG2-MAIN relay) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (IG2-MAIN RELAY - ECM) 
    1. Remove the IG2-MAIN 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
      5 (IG2-MAIN relay) - A35-37 (IGSW) Always Below 1 Ω
      5 (IG2-MAIN relay) or A35-37 (IGSW) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. INSPECT EFI-MAIN RELAY 
    1. Inspect the EFI-MAIN relay.

      Refer to PROCEDURE - Step 2

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE EFI-MAIN RELAY 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (AUXILIARY BATTERY - EFI-MAIN RELAY) 
    GTY506299Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 No. 1 Engine Room Relay Block and Junction Block Assembly
    *2 EFI-MAIN Relay
    1. Remove the EFI-MAIN relay from the No. 1 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
      5 (EFI-MAIN relay) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (EFI-MAIN RELAY - BODY GROUND) 
    1. Remove the EFI-MAIN relay from the No. 1 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
      2 (EFI-MAIN relay) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  9

  9. CHECK HARNESS AND CONNECTOR (EFI-MAIN RELAY - ECM) 
    1. Remove the EFI-MAIN 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
      3 (EFI-MAIN relay) - A35-2 (+B) Always Below 1 Ω
      3 (EFI-MAIN relay) - A35-3 (+B2) Always Below 1 Ω
      1 (EFI-MAIN relay) - A35-46 (MREL) Always Below 1 Ω
      3 (EFI-MAIN relay) or A35-2 (+B) - Body ground Always 10 kΩ or higher
      3 (EFI-MAIN relay) or A35-3 (+B2) - Body ground Always 10 kΩ or higher
      1 (EFI-MAIN relay) or A35-46 (MREL) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  10

  10. 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
      C48-16 (E1) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [10/2014 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  11. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - IG2-MAIN RELAY) 
    1. Disconnect the Certification ECU (smart key ECU assembly) connector.
    2. Remove the IG2-MAIN relay from the No. 1 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
      I51-3 (IG1D) - 1 (IG2-MAIN relay) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2014 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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