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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 ECM connectors.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      +B (E5-1) - E1 (E9-1) 9 to 14 V
      +B2 (E5-2) - E1 (E9-1) 9 to 14 V

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

    Fig 1: Identifying ECM Connector Terminal (+B Voltage)
    G05245767Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to Next Step 

  2. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the 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 CHART

      Tester Connection Specified Condition
      E1 (E9-1) - Body ground Below 1 Ω
    3. Reconnect the ECM connector.
      Fig 2: Identifying ECM Connector Terminal (ECM - Body Ground)
      G05245768Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    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 ECM connectors.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      IGSW (E5-9) - E1 (E9-1) 9 to 14 V

    OK:  Go to step  6

    Fig 3: Identifying ECM Connector Terminal (IGSW Voltage)
    G05245769Courtesy 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: REPLACE FUSE (IGN FUSE) 

    Fig 4: Locating IGN Fuse From Instrument Panel J/B
    G05245770Courtesy 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 

    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 between the terminals of the ECM connectors.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      MREL (E5-8) - E1 (E9-1) 9 to 14 V

    NG: REPLACE ECM 

    Fig 5: Identifying ECM Connector Terminal (MREL Voltage)
    G05245771Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  7. CHECK FUSE (EFI NO. 1 FUSE) 
    1. Remove the EFI No. 1 fuse from the engine room J/B.
    2. Measure the EFI No. 1 fuse resistance.

      Standard resistance: Below 1 Ω 

    3. Reinstall the EFI No. 1 fuse.

    NG: REPLACE FUSE (EFI NO. 1 FUSE) 

    Fig 6: Locating EFI No. 1 Fuse From Engine Room J/B
    G05245678Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  8. INSPECT EFI RELAY 
    1. Remove the EFI relay from the engine room J/B.
    2. Measure the EFI relay resistance.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      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)
    3. Reinstall the EFI relay.
      Fig 7: Inspecting EFI Relay
      G04942983Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE EFI RELAY 

    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 J/B.
      2. Disconnect the ECM connector.
      3. Measure the resistance according to the value (s) in the table below.

        Standard resistance: Check for open 

        TESTER CONNECTION SPECIFIED CONDITION CHART

        Tester Connection Specified Condition
        EFI relay terminal (1) - MREL (E5-8) Below 1 Ω
        Fig 8: Identifying ECM Connector Terminal
        G05245774Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Check for short 

        TESTER CONNECTION SPECIFIED CONDITION CHART

        Tester Connection Specified Condition
        EFI relay terminal (1) or MREL (E5-8) - Body ground 10 kΩ or higher
    2. Check the harness and connector between the EFI relay and body ground.
      1. Measure the resistance according to the value (s) in the table below.

        Standard resistance: 

        Check for open 

        TESTER CONNECTION SPECIFIED CONDITION CHART

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

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR 

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

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