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Ignition Circuit [12/2017 - 10/2020]: Procedure

  1. CHECK TERMINAL VOLTAGE (POWER SOURCE OF IGNITION COIL ASSEMBLY) 
    1. Disconnect the ignition coil assembly connectors.
    2. Turn the engine switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      F1-1 (+B) - F1-3 (GND) Engine switch on (IG) 11 to 14 V
      F4-1 (+B) - F4-3 (GND) Engine switch on (IG) 11 to 14 V
      F2-1 (+B) - F2-3 (GND) Engine switch on (IG) 11 to 14 V
      F5-1 (+B) - F5-3 (GND) Engine switch on (IG) 11 to 14 V
      D4-1 (+B) - D4-3 (GND) Engine switch on (IG) 11 to 14 V
      D5-1 (+B) - D5-3 (GND) Engine switch on (IG) 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  3

    Result: 

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (IGNITION COIL ASSEMBLY - ECM) 
    1. Disconnect the ignition coil assembly connectors.
    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
      F1-2 (IGT1) - D1-61 (IGT1) Always Below 1 Ω
      F4-2 (IGT2) - D1-60 (IGT2) Always Below 1 Ω
      F2-2 (IGT3) - D1-59 (IGT3) Always Below 1 Ω
      F5-2 (IGT4) - D1-58 (IGT4) Always Below 1 Ω
      D4-2 (IGT5) - D1-57 (IGT5) Always Below 1 Ω
      D5-2 (IGT6) - D1-56 (IGT6) Always Below 1 Ω
      F1-2 (IGT1) or D1-61 (IGT1) - Body ground and other terminals Always 10 kΩ or higher
      F4-2 (IGT2) or D1-60 (IGT2) - Body ground and other terminals Always 10 kΩ or higher
      F2-2 (IGT3) or D1-59 (IGT3) - Body ground and other terminals Always 10 kΩ or higher
      F5-2 (IGT4) or D1-58 (IGT4) - Body ground and other terminals Always 10 kΩ or higher
      D4-2 (IGT5) or D1-57 (IGT5) - Body ground and other terminals Always 10 kΩ or higher
      D5-2 (IGT6) or D1-56 (IGT6) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM. Refer to  REMOVAL [12/2017 - 09/2018]  , or refer to  REMOVAL [09/2018 - 10/2020] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  3. CHECK HARNESS AND CONNECTOR (IGNITION COIL ASSEMBLY - BODY GROUND) 
    1. Disconnect the ignition coil assembly connectors.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F1-3 (GND) - Body ground Always Below 1 Ω
      F4-3 (GND) - Body ground Always Below 1 Ω
      F2-3 (GND) - Body ground Always Below 1 Ω
      F5-3 (GND) - Body ground Always Below 1 Ω
      D4-3 (GND) - Body ground Always Below 1 Ω
      D5-3 (GND) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (IG2 RELAY - IGNITION COIL ASSEMBLY) 
    1. Disconnect the IG2 relay from the No. 1 engine room relay block and junction block assembly.
    2. Disconnect the ignition coil assembly connectors.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      5 (IG2 relay) - F1-1 (+B) Always Below 1 Ω
      5 (IG2 relay) - F4-1 (+B) Always Below 1 Ω
      5 (IG2 relay) - F2-1 (+B) Always Below 1 Ω
      5 (IG2 relay) - F5-1 (+B) Always Below 1 Ω
      5 (IG2 relay) - D4-1 (+B) Always Below 1 Ω
      5 (IG2 relay) - D5-1 (+B) Always Below 1 Ω
      5 (IG2 relay) or F1-1 (+B) - Body ground and other terminals Always 10 kΩ or higher
      5 (IG2 relay) or F4-1 (+B) - Body ground and other terminals Always 10 kΩ or higher
      5 (IG2 relay) or F2-1 (+B) - Body ground and other terminals Always 10 kΩ or higher
      5 (IG2 relay) or F5-1 (+B) - Body ground and other terminals Always 10 kΩ or higher
      5 (IG2 relay) or D4-1 (+B) - Body ground and other terminals Always 10 kΩ or higher
      5 (IG2 relay) or D5-1 (+B) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

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

      Refer to ON-VEHICLE INSPECTION [12/2017 - 10/2023]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE IG2 RELAY 

    Result: 

    OK 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (POWER SOURCE OF IG2 RELAY) 
    GTY806050Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 No. 1 Engine Room Relay Block and Junction Block Assembly
    *2 IG2 Relay
    1. Remove the IG2 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 relay) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

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

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (IG2 RELAY - BODY GROUND) 
    1. Remove the IG2 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 relay) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START (FOR START FUNCTION). Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2017 - 10/2022] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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