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Inspection Procedure

  1. INSPECT ECM (+B VOLTAGE) 
    1. Turn the ignition switch ON.
    2. Measure the voltage between the terminals of the ECM connectors.

    Standard voltage 

    TESTER CONNECTION - SPECIFIED CONDITIONS

    Tester Connection Specified Condition
    +B (E3-1) - E1 (E5-3) 9 to 14 V

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

    Fig 1: Measuring Voltage Between Terminals Of ECM Connectors
    G04225680Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to Next Step 

  2. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the negative (-) battery cable.
    2. Disconnect the E5 ECM connector.
    3. Measure the resistance of the wire harness side connector.

    Standard resistance (Check for open) 

    TESTER CONNECTION - SPECIFIED CONDITIONS

    Tester Connection Specified Condition
    E1 (E5-3) - Body ground Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 2: Measuring Resistance Of Wire Harness Side Connector
    G04225681Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  3. INSPECT ECM (IGSW VOLTAGE) 
    1. Turn the ignition switch ON.
    2. Measure the voltage of the ECM connectors.

    Standard voltage 

    TESTER CONNECTION - SPECIFIED CONDITIONS

    Tester Connection Specified Condition
    IGSW (E3-9) - E1 (E5-3) 9 to 14 V

    OK: Go to step   6 

    Fig 3: Measuring Voltage Of ECM Connectors
    G04225682Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to Next Step 

  4. CHECK FUSE (AM2) 
    1. Remove the AM2 fuse from the engine room relay block.
    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 

    Fig 4: Measuring Resistance Of AM2 Fuse
    G04225683Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  5. INSPECT IGNITION SWITCH ASSEMBLY 
    1. Disconnect the I10 ignition switch connector.
    2. Measure the resistance of the ignition switch.

    Standard resistance 

    TESTER CONNECTION - SPECIFIED CONDITIONS

    Ignition Switch Position Tester Connection Specified Condition
    LOCK All Terminals 10 kΩ or higher
    ON AM2 (5) - IG2 (6) Below 1 Ω

    NG: REPLACE IGNITION SWITCH ASSEMBLY 

    Fig 5: Measuring Resistance Of Ignition Switch
    G04225684Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

  6. INSPECT ECM (MREL VOLTAGE) 
    1. Turn the ignition switch ON.
    2. Measure the voltage of the ECM connectors.

    Standard voltage 

    TESTER CONNECTION - SPECIFIED CONDITIONS

    Tester Connection Specified Condition
    MREL (E3-8) - E1 (E5-3) 9 to 14 V

    NG: REPLACE ECM 

    Fig 6: Measuring Voltage Of ECM Connectors
    G04225685Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  7. CHECK FUSE (EFI) 
    1. Remove the EFI fuse from the engine room relay block.
    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 

    Fig 7: Measuring Resistance Of EFI Fuse
    G04225686Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  8. INSPECT EFI RELAY (Marking: EFI) 
    1. Remove the EFI relay from the engine room relay block.
    2. Measure the resistance of the EFI fuse.

    Standard resistance 

    TESTER CONNECTION - 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 

    Fig 8: Measuring Resistance Of EFI Fuse
    G04225687Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  9. CHECK HARNESS AND CONNECTOR (EFI RELAY - ECM, EFI RELAY - BODY GROUND) 
    1. Check the harness and connector between the EFI relay and ECM.
      1. Remove the EFI relay from the engine room relay block.
        Fig 9: Checking Harness And Connector Between EFI Relay And ECM
        G04225688Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Disconnect the E3 ECM connector.
      3. Measure the resistance of the wire harness side connectors.

        Standard resistance (Check for open) 

        TESTER CONNECTION - SPECIFIED CONDITIONS

        Tester Connections Specified Conditions
        Engine room relay block (EFI relay terminal 2) - MREL (E3-8) Below 1 Ω
        Engine room relay block (EFI relay terminal 3) - +B (E3-1) Below 1 Ω
        Fig 10: Measuring Resistance Of Wire Harness Side Connectors
        G04225689Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard resistance (Check for short) 

        TESTER CONNECTION - SPECIFIED CONDITIONS

        Tester Connections Specified Conditions
        Engine room relay block (EFI relay terminal 2) or MREL (E3-8) - Body ground 10 kΩ or higher
        Engine room relay block (EFI relay terminal 3) or +B (E3-1) - Body ground 10 kΩ or higher
    2. Check the harness and connector between the EFI relay and body ground.
      1. Remove the EFI relay from the engine room relay block.
      2. Measure the resistance of the wire harness side connector.

        Standard resistance (Check for open) 

        TESTER CONNECTION - SPECIFIED CONDITIONS

        Tester Connection Specified condition
        Engine room relay block (EFI relay terminal 1) - Body ground Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

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

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