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Inspection Procedure

  1. INSPECT ECM (+B VOLTAGE) 
    1. Turn the ignition switch to the ON position.
    2. Measure the voltage between the terminals of the E5 and E7 ECM connectors.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      +B (E5-1) - E1 (E7-1) 9 to 14 V

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

    Fig 1: Identifying ECM Connector Terminals
    G05268232Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to Next Step 

  2. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the E7 ECM connector.
    2. Measure the resistance between the terminal of the ECM connector and body ground.

      Standard resistance: 

      Check for open 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      E1 (E7-1) - Body ground Below 1 Ω
    3. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 2: Identifying ECM Connector Terminal
    G05268233Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  3. INSPECT ECM (IGSW VOLTAGE) 
    1. Turn the ignition switch to the ON position.
    2. Measure the voltage between the terminals of the E5 and E7 ECM connectors.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      IGSW (E5-9) - E1 (E7-1) 9 to 14 V

    OK: Go to step  6

    Fig 3: Identifying ECM Connector Terminals
    G05268234Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to Next Step 

  4. CHECK FUSE (IGN FUSE) 
    1. Remove the IGN fuse from the instrument panel J/B.
    2. Measure the IGN fuse resistance.

      Standard resistance: 

      Below 1 Ω 

    3. Reinstall the IGN fuse.

    NG: CHECK FOR SHORTS IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

    Fig 4: Identifying IGN Fuse Location
    G05268235Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  5. INSPECT IGNITION OR STARTER SWITCH ASSEMBLY 
    1. Inspect the ignition or starter switch assembly (See INSPECTION ).

    NG: REPLACE IGNITION OR STARTER SWITCH ASSEMBLY  (See REMOVAL )

    OK: Go to Next Step 

  6. INSPECT ECM (MREL VOLTAGE) 
    1. Turn the ignition switch to the ON position.
    2. Measure the voltage between the terminals of the E5 and E7 ECM connectors.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      MREL (E5-8) - E1 (E7-1) 9 to 14 V

    NG: REPLACE ECM  (See REMOVAL  )

    Fig 5: Identifying ECM Connector Terminals
    G05268236Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  7. CHECK FUSE (EFI FUSE) 
    1. Remove the EFI No. 1 fuse from the fusible link block.
    2. Measure the EFI No. 1 fuse resistance.

      Standard resistance: 

      Below 1 Ω 

    3. Reinstall the EFI No. 1 fuse.

    NG: CHECK FOR SHORTS IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

    Fig 6: Identifying EFI No. 1 Fuse Location
    G05268237Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  8. INSPECT EFI MAIN RELAY 
    1. Remove the EFI MAIN relay from the fusible link block.
    2. Measure the EFI MAIN relay resistance.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      3 - 5 10 kΩ or higher
      3 - 5 Below 1 Ω (when battery voltage applied to terminals 1 and 2)
    3. Reinstall the EFI MAIN relay.

    NG: REPLACE EFI MAIN RELAY 

    Fig 7: Identifying EFI Main Relay Terminals
    G04942983Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  9. CHECK HARNESS AND CONNECTOR (EFI MAIN RELAY - ECM, EFI MAIN RELAY - BODY GROUND) 
    1. Check the harness and connector between the EFI MAIN relay and ECM.
      1. Remove the EFI MAIN relay from the engine room R/B.
      2. Disconnect the E5 ECM connector.
      3. Measure the resistance between the terminals.

        Standard resistance: 

        Check for open 

        TESTER CONNECTION SPECIFIED CONDITION

        Tester Connection Specified Condition
        EFI MAIN relay terminal (1) - MREL (E5-8) Below 1 Ω

        Check for short 

        TESTER CONNECTION SPECIFIED CONDITION

        Tester Connection Specified Condition
        EFI MAIN relay terminal (1) or MREL (E5-8) - Body ground 10 kΩ or higher
    2. Check the harness and connector between the EFI MAIN relay and body ground.
      1. Measure the resistance between the terminals.

        Standard resistance : 

        Check for open 

        TESTER CONNECTION SPECIFIED CONDITION

        Tester Connection Specified Condition
        EFI MAIN relay terminal (2) - Body ground Below 1 Ω
      2. Reinstall the engine room R/B.
      3. Reconnect the ECM connector.

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 8: Identifying EFI Main Relay And ECM Connector Terminals
    G05268239Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: CHECK AND REPLACE HARNESS AND CONNECTOR (TERMINAL +B OF ECM - BATTERY POSITIVE TERMINAL) 

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