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Inspection Procedure

  1. INSPECT ECM (+B VOLTAGE) 
    1. Disconnect the E4 and E8 ECM connectors.
      2. Fig 1: Identifying E4 And E8 ECM Connectors
      G05539152Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the ignition switch to the ON position.
    3. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      VOLTAGE SPECIFIED CONDITION

      Tester Connection Specified Condition
      +B (E4-1) - E1 (E8-3) 9 to 14 V

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE 

    NG: go to next step 

  2. CHECK WIRE HARNESS (ECM - BODY GROUND) 
    1. Disconnect the negative battery cable.
    2. Disconnect the E8 ECM connector.
      3. Fig 2: Identifying ECM Connector
      G05128297Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      E1 (E8-3) - Body ground Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: go to next step 

  3. INSPECT ECM (IGSW VOLTAGE) 
    1. Disconnect the E4 and E8 ECM connectors.
      2. Fig 3: Identifying IGSW And E1 Terminal Of ECM Connector
      G05128302Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the ignition switch to the ON position.
    3. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      VOLTAGE SPECIFIED CONDITION

      Tester Connection Specified Condition
      IGSW (E4-9) - E1 (E8-3) 9 to 14 V

    OK:  Go to step  6

    NG: go to next step 

  4. CHECK FUSE (AM2) 
    1. Remove the AM2 fuse from the engine room relay block.
      2. Fig 4: Identifying AM2 Fuse
      G05539155Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance of the AM2 fuse.

      Standard resistance: 

      Below 1 Ω 

    NG: CHECK FOR SHORT IN ALL HARNESSES AND COMPONENTS CONNECTED TO FUSE 

    OK: go to next step 

  5. INSPECT IGNITION SWITCH ASSEMBLY 
    1. Disconnect the 15 ignition switch connector.
      2. Fig 5: Identifying AM2 And IG2 Terminal Of Ignition Switch Connector
      G05539156Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFIED CONDITIONS

      Switch Position Tester Connection Specified Condition
      LOCK All Terminals 10 kΩ or higher
      ON IG2 (6) - AM2 (7) Below 1 Ω

    NG: REPLACE IGNITION SWITCH ASSEMBLY 

    OK: CHECK AND REPLACE HARNESS AND CONNECTOR (BATTERY - IGNITION SWITCH, IGNITION SWITCH - ECM) 

  6. INSPECT ECM (MREL VOLTAGE) 
    1. Turn the ignition switch to the ON position.
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      VOLTAGE SPECIFIED CONDITION

      Tester Connection Specified Condition
      MREL (E4-8) - E1 (E8-3) 9 to 14 V
      Fig 6: Identifying MREL And E1 Terminal Of ECM Connector
      G05539157Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE ECM 

    OK: go to next step 

  7. CHECK FUSE (EFI) 
    1. Remove the EFI fuse from the engine room relay block.
      2. Fig 7: Identifying EFI Fuse
      G05539065Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance of the EFI fuse.

      Standard resistance: 

      Below 1 Ω 

    NG: CHECK FOR SHORT IN ALL HARNESSES AND COMPONENTS CONNECTED TO FUSE 

    OK: go to next step 

  8. INSPECT EFI RELAY (EFI) 
    1. Remove the EFI relay from the engine room relay block.
      2. Fig 8: Identifying EFI Relay
      G04978973Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      3 - 5 10 kΩ or higher
      3 - 5 Below 1 Ω (when battery voltage is applied to terminals 1 and 2)

    NG: REPLACE EFI RELAY 

    OK: go to next step 

  9. CHECK WIRE HARNESS (EFI RELAY - ECM, BODY GROUND) 
    1. Check the wire harness between the EFI relay and ECM.
      1. Remove the EFI relay from the engine room relay block.
      2. Disconnect the E4 ECM connector.
      3. Measure the resistance according to the value(s) in the table below.

        Standard resistance 

        RESISTANCE SPECIFIED CONDITIONS

        Tester Connection Specified Condition
        Engine room relay block (EFI relay terminal 1) - MREL (E4-8) Below 1 Ω
        Engine room relay block (EFI relay terminal 3) - +B (E4-1) Below 1 Ω
        Engine room relay block (EFI relay terminal 1) or MREL (E4-8) - Body ground 10 kΩ or higher
        Engine room relay block (EFI relay terminal 3) or +B (E4-1) - Body ground 10 kΩ or higher
    2. Check the wire harness between the EFI relay and body ground.
      1. Remove the EFI relay from the engine room relay block.
        2. Fig 9: Identifying EFI Relay And ECM Connector
        G05539160Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Measure the resistance according to the value(s) in the table below.

        Standard resistance 

        RESISTANCE SPECIFIED CONDITIONS

        Tester Connection Specified Condition
        Engine room relay block (EFI relay terminal 2) - Body ground Below 1 Ω
      3. Reinstall the EFI relay.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: CHECK AND REPAIR HARNESS AND CONNECTOR (TERMINAL 5 OF EFI RELAY - BATTERY POSITIVE TERMINAL) 

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