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Inspection Procedure

  1. PERFORM ACTIVE TEST BY INTELLIGENT TESTER (OPERATION OF CIRCUIT OPENING RELAY) 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the ignition switch ON and turn the tester ON.
    3. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / FUEL PUMP / SPD.
    4. Check whether operating sounds can be heard while operating the relay using the tester.

      OK: Operating sounds can be heard from relay. 

    OK: Go to step   7 

    NG: Go to Next Step 

  2. INSPECT ECM POWER SOURCE CIRCUIT 
    1. Inspect the ECM power source circuit (see ECM POWER SOURCE CIRCUIT  ).

    NG: REPAIR OR REPLACE 

    OK: Go to Next Step 

  3. INSPECT CIRCUIT OPENING RELAY (Marking: C/OPN) 
    1. Remove the circuit opening relay from the instrument panel junction block.
    2. Measure the resistance of the circuit opening relay.

      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 CIRCUIT OPENING RELAY 

    Fig 1: Inspecting ECM Power Source Circuit
    G04225696Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  4. INSPECT ECM (FC 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
      FC (E3-25) - E01 (E5-7) 9 to 14 V

    OK: REPLACE ECM 

    Fig 2: Measuring Voltage Of ECM Connectors
    G04225697Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to Next Step 

  5. CHECK HARNESS AND CONNECTOR (EFI RELAY (Marking: EFI) - CIRCUIT OPENING RELAY (Marking: C/OPN) 
    1. Remove the EFI relay from the engine room relay block.
      Fig 3: Removing EFI Relay From Engine Room Relay Block
      G04225698Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Remove the circuit opening relay from the instrument panel junction block.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance (Check for open) 

      Fig 4: Removing Circuit Opening Relay From Instrument Panel Junction Block
      G04225699Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TESTER CONNECTION - SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      Engine room relay block (EFI relay terminal 3) - Instrument panel junction block (Circuit opening relay terminal 1) Below 1 Ω
      Engine room relay block (EFI relay terminal 3) - Instrument panel junction block (Circuit opening relay terminal 5) Below 1 Ω

      Standard resistance (Check for short) 

      TESTER CONNECTION - SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      Engine room relay block (EFI relay terminal 3) or Circuit opening relay (1) - Body ground 10 kΩ or higher
      Instrument panel junction block (Circuit opening relay terminal 5) - Body ground 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

  6. CHECK HARNESS AND CONNECTOR (ECM - CIRCUIT OPENING RELAY) 
    1. Disconnect the E3 ECM connector.
      Fig 5: Disconnecting E3 ECM Connector
      G04225700Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Remove the circuit opening relay from the instrument panel junction block.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance (Check for open) 

      Fig 6: Measuring Resistance Of Wire Harness Side Connectors
      G04225701Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TESTER CONNECTION - SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      FC (E3-25) - Instrument panel junction block (Circuit opening relay terminal 2) Below 1 Ω

      Standard resistance (Check for short) 

      TESTER CONNECTION - SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      FC (E3-25) or Instrument panel junction block (Circuit opening relay terminal 2) - Body ground 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE ECM 

  7. INSPECT FUEL PUMP 
    1. Inspect the fuel pump (see INSPECTION ).

    NG: REPLACE FUEL PUMP 

    OK: Go to Next Step 

  8. CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY (Marking: C/OPN) - FUEL PUMP, FUEL PUMP - BODY GROUND) 
    1. Remove the circuit opening relay from the instrument panel junction block.
    2. Disconnect the F14 fuel pump connector.
      Fig 7: Disconnecting F14 Fuel Pump Connector
      G04225702Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance of the wire harness side connectors.
      Fig 8: Measuring Resistance Of Wire Harness Side Connectors
      G04225703Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance (Check for open) 

      TESTER CONNECTION - SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      Instrument panel junction block (Circuit opening relay terminal 3) - Fuel pump (F14-4) Below 1 Ω
      Fuel pump (F14-5) - Body ground Below 1 Ω

      Standard resistance Check for short) 

      TESTER CONNECTION - SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      Instrument panel junction block (Circuit opening relay terminal 3) or Fuel pump (F14-4) - Body ground 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE ECM 

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