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Ignition Circuit [11/2021 - ]: Procedure

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  1. CHECK TERMINAL VOLTAGE (POWER SOURCE OF IGNITION COIL ASSEMBLY) 
    1. Disconnect the ignition coil assembly connectors.
    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
      B5-1 (+B) - B5-3 (GND) Ignition switch ON 11 to 14 V
      B6-1 (+B) - B6-3 (GND) Ignition switch ON 11 to 14 V
      B7-1 (+B) - B7-3 (GND) Ignition switch ON 11 to 14 V
      B8-1 (+B) - B8-3 (GND) Ignition switch ON 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
      B5-2 (IGT1) - B49-61 (IGT1) Always Below 1 Ω
      B6-2 (IGT2) - B49-60 (IGT2) Always Below 1 Ω
      B7-2 (IGT3) - B49-59 (IGT3) Always Below 1 Ω
      B8-2 (IGT4) - B49-58 (IGT4) Always Below 1 Ω
      B5-2 (IGT1) or B49-61 (IGT1) - Body ground and other terminals Always 10 kΩ or higher
      B6-2 (IGT2) or B49-60 (IGT2) - Body ground and other terminals Always 10 kΩ or higher
      B7-2 (IGT3) or B49-59 (IGT3) - Body ground and other terminals Always 10 kΩ or higher
      B8-2 (IGT4) or B49-58 (IGT4) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM. Refer to  REMOVAL [11/2021 - ] 

    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
      B5-3 (GND) - Body ground Always Below 1 Ω
      B6-3 (GND) - Body ground Always Below 1 Ω
      B7-3 (GND) - Body ground Always Below 1 Ω
      B8-3 (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. INSPECT INJ RELAY 
    1. Inspect the INJ relay.

      Refer to PROCEDURE - Step 1

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE INJ RELAY 

    Result: 

    OK 

    See step  5

  5. CHECK TERMINAL VOLTAGE (POWER SOURCE OF INJ RELAY) 
    1. Remove the INJ relay from the No. 1 engine room relay block and No. 1 junction block assembly.
      GTY1253940Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly
      *2 INJ Relay
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      3 (INJ relay) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

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

    Result: 

    OK 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (INJ RELAY - BODY GROUND) 
    1. Remove the INJ relay from the No. 1 engine room relay block and No. 1 junction block assembly.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1 (INJ relay) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (INJ RELAY - IGNITION COIL ASSEMBLY) 
    1. Disconnect the INJ relay from No. 1 engine room relay block and No. 1 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 (INJ relay) - B5-1 (+B) Always Below 1 Ω
      5 (INJ relay) - B6-1 (+B) Always Below 1 Ω
      5 (INJ relay) - B7-1 (+B) Always Below 1 Ω
      5 (INJ relay) - B8-1 (+B) Always Below 1 Ω
      5 (INJ relay) or B5-1 (+B) - Body ground and other terminals Always 10 kΩ or higher
      5 (INJ relay) or B6-1 (+B) - Body ground and other terminals Always 10 kΩ or higher
      5 (INJ relay) or B7-1 (+B) - Body ground and other terminals Always 10 kΩ or higher
      5 (INJ relay) or B8-1 (+B) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    GO TO ECM POWER SOURCE CIRCUIT. Refer to  ECM Power Source Circuit [11/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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