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ECM Power Source Circuit [08/2013 - ]: Procedure

WARNING: This page is about a different variant/trim than selected.
  1. 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
      B33-16 (E1) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result:  2

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  1

    OK 

    See step  2

  2. CHECK TERMINAL VOLTAGE (IGSW TERMINAL VOLTAGE) 
    1. Disconnect the ECM connector.
      GTY434505Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to ECM)
    2. Turn the ignition switch to ON.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A40-37 (IGSW) - Body ground Ignition switch ON 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result:  2

    NG 

    See step  7

    Result:  1

    OK 

    See step  3

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

      Refer to PROCEDURE - Step 2

      Result

      Proceed to
      OK
      NG

    Result:  2

    NG 

    REPLACE EFI-MAIN RELAY 

    Result:  1

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (ECM - EFI-MAIN RELAY) 
    1. Disconnect the ECM connector.
    2. Remove the EFI-MAIN relay from the 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
      A40-46 (MREL) - 1 (EFI-MAIN relay) Always Below 1 Ω
      A40-2 (+B) - 3 (EFI-MAIN relay) Always Below 1 Ω
      A40-3 (+B2) - 3 (EFI-MAIN relay) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result:  2

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  1

    OK 

    See step  5

  5. CHECK TERMINAL VOLTAGE (POWER SOURCE OF EFI-MAIN RELAY) 
    1. Remove the EFI-MAIN relay from the engine room relay block and junction block assembly.
      GTY454494Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Engine Room Relay Block and Junction Block Assembly
      *2 EFI-MAIN Relay
    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:  2

    NG 

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

    Result:  1

    OK 

    See step  6

  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
      2 (EFI-MAIN relay) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result:  1

    OK 

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [08/2013 - 08/2016]  Refer to  PROBLEM SYMPTOMS TABLE [08/2016 - ] 

    Result:  2

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  7. INSPECT IG2 RELAY 
    1. Inspect the IG2 relay.

      Refer to PROCEDURE - Step 1

      Result

      Proceed to
      OK
      NG

    Result:  2

    NG 

    REPLACE IG2 RELAY 

    Result:  1

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (ECM - IG2 RELAY) 
    1. Disconnect the ECM connector.
    2. Remove the IG2 relay from the 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
      A40-37 (IGSW) - 3 (IG2 relay) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result:  2

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  1

    OK 

    See step  9

  9. CHECK TERMINAL VOLTAGE (POWER SOURCE OF IG2 RELAY) 
    1. Remove the IG2 relay from the engine room relay block and junction block assembly.
      GTY440177Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Engine Room Relay Block and Junction Block Assembly
      *2 IG2 Relay
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      5 (IG2 relay) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result:  2

    NG 

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

    Result:  1

    OK 

    See step  10

  10. 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
      1 (IG2 relay) - Body ground Always Below 1 Ω

      Result

      Result Proceed to
      OK (w/ smart key system) A
      OK (w/o smart key system) B
      NG C

    Result:  2

    B 

    See step  12

    Result:  3

    C 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  1

    A 

    See step  11

  11. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - IG2 RELAY) 
    1. Disconnect the certification ECU (smart key ECU assembly) connector.
    2. Remove the IG2 relay from the 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
      E57-9 (IG2D) - 2 (IG2 relay) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result:  1

    OK 

    GO TO SMART KEY SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2013 - 08/2016]  Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2016 - ] 

    Result:  2

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  12. INSPECT IGNITION SWITCH ASSEMBLY 
    1. Inspect the ignition switch assembly.

      Refer to INSPECTION [08/2013 - ]

      Result

      Proceed to
      OK
      NG

    Result:  2

    NG 

    REPLACE IGNITION SWITCH ASSEMBLY. Refer to  REMOVAL [08/2013 - ] 

    Result:  1

    OK 

    See step  13

  13. CHECK HARNESS AND CONNECTOR (IGNITION SWITCH ASSEMBLY - IG2 RELAY) 
    1. Disconnect the ignition switch assembly connector.
    2. Remove the IG2 relay from the 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
      E4-3 (IG2) - 2 (IG2 relay) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result:  1

    OK 

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

    Result:  2

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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