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Inspection Procedure

  1. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (FUEL PUMP/SPD) 
    1. Connect an intelligent tester to the DLC3.
    2. Turn the ignition switch to ON and turn the tester ON.
    3. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / FUEL PUMP/ SPD.
    4. Check whether the fuel pump operating sound occurs when perform the Active Test on the tester.

      OK: Fuel pump operating sound occurs. 

    OK: Go to step   8 

    NG: GO TO NEXT STEP 

  2. INSPECT MAIN BODY ECU (C/OPN RELAY INPUT VOLTAGE) 
    1. Measure the voltage between the terminal of the main body ECU and the body ground when the ignition switch is turned to ON and OFF.

      Standard voltage 

      VOLTAGE SPECIFICATION

      Tester Connections Ignition Switch Conditions Specified Conditions
      4B-11 - Body ground OFF Below 1 V
      4F-4 - Body ground
      4B-11 - Body ground ON 11 to 14 V
      4F-4 - Body ground

    OK: Go to step   4 

    Fig 1: Identifying Main Body ECU Terminals
    G04828340Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: GO TO NEXT STEP 

  3. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - INTEGRATION RELAY) 
    1. Remove the integration relay from the engine room relay block.
    2. Disconnect the main body ECU connector.
    3. Check the resistance.

      Standard resistance (Check for open) 

      RESISTANCE SPECIFICATION

      Tester Connections Specified Conditions
      1B-4 - 4F-4 Below 1 Ω
      1A-4 - 4B-11

      Standard resistance (Check for short) 

      RESISTANCE SPECIFICATION

      Tester Connections Specified Conditions
      4F-4 - Body ground 10 kΩ or higher
      4B-11 - Body ground
    4. Reinstall the integration relay.
    5. Reconnect the main body ECU connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 2: Identifying Main Body ECU & Integration Relay Connectors
    G04828341Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: GO TO  ECM POWER SOURCE CIRCUIT  

  4. INSPECT MAIN BODY ECU (C/OPN RELAY) 
    1. Remove the main body ECU.
    2. Check the C/OPN relay resistance.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connections Specified Conditions
      4B-11 - 4A-8 10 kΩ or higher
      Below 1 Ω (when battery voltage is applied to terminals 4D-1 and 4E-5)

      HINT:

      Relay coil circuit between 4D-1 and 4E-5 is not through IGN fuse.

    3. Reinstall the main body ECU.

    NG: REPLACE MAIN BODY ECU 

    Fig 3: Identifying Main Body ECU Connectors
    G04828342Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: GO TO NEXT STEP 

  5. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - ECM) 
    1. Disconnect the A21 ECM connector.
    2. Disconnect the 4E connector from main body ECU.
    3. Check the resistance.

      Standard resistance (Check for open) 

      RESISTANCE SPECIFICATION

      Tester Connections Specified Conditions
      Main Body ECU (4E-5) - FC (A21-7) Below 1 Ω

      Standard resistance (Check for short) 

      RESISTANCE SPECIFICATION

      Tester Connections Specified Conditions
      Main body ECU (4E-5) or FC (A21-7) - Body ground 10 kΩ or higher
    4. Reconnect the main body ECU and the ECM connectors.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 4: Identifying Main Body ECU & ECM Connectors
    G04828343Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: GO TO NEXT STEP 

  6. CHECK HARNESS AND CONNECTOR (C/OPN RELAY - FUEL PUMP - BODY GROUND) 
    1. Check the harness and the connectors between the main body ECU and the fuel pump.
      1. Disconnect the 4A main body ECU connector.
      2. Disconnect the J5 fuel pump connector.
      3. Check the resistance.

        Standard resistance (Check for open) 

        RESISTANCE SPECIFICATION

        Tester Connections Specified Conditions
        Main body ECU (4A-8) - Fuel pump (J5-4) Below 1 Ω

        Standard resistance (Check for short) 

        RESISTANCE SPECIFICATION

        Tester Connections Specified Conditions
        Main body ECU (4A-8) or Fuel pump (J5-4) - Body ground 10 kΩ or higher
    2. Check the harness and the connectors between the fuel pump and the body ground.
      1. Disconnect the J5 fuel pump connector.
      2. Check the resistance.

        Standard resistance (Check for open) 

        RESISTANCE SPECIFICATION

        Tester Connections Specified Conditions
        Fuel pump (J5-5) - Body ground Below 1 Ω
    3. Reconnect the main body ECU connector.
    4. Reconnect the fuel pump connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 5: Identifying Fuel Pump & Main Body ECU Connector Connectors
    G04828344Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: GO TO NEXT STEP 

  7. INSPECT FUEL PUMP 
    1. Inspect fuel pump resistance.
      1. Measure the resistance between the terminals.

        Standard resistance: 0.2 to 3.0 Ω at 20°C (68°F) 

    2. Inspect fuel pump operation.
      1. Apply the battery voltage to both the terminals. Check that the pump operates.
        NOTE:
        • These tests must be done quickly (within 10 seconds) to prevent the coil from burning out.
        • Keep the fuel pump as far away from the battery as possible.
          Fig 6: Identifying Fuel Pump Terminals
          G04828345Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        • Always switch at the battery side.

    NG: REPLACE FUEL PUMP 

    OK: REPLACE ECM 

  8. READ VALUE USING INTELLIGENT TESTER (STARTER SIG) 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the ignition switch to ON and turn the tester ON.
    3. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / PRIMARY / STARTER SIG.
    4. Check the result when the ignition switch is turned to ON and START.

      Standard 

      RESULT REFERENCE

      Ignition Switch Position ON START
      Starter Signal OFF ON

    NG: REPAIR OR REPLACE STARTING SYSTEM 

    OK: GO TO NEXT STEP 

  9. READ VALUE USING INTELLIGENT TESTER (ENGINE SPD) 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the ignition switch to ON and turn the tester ON.
    3. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / PRIMARY / ENGINE SPD.
    4. Read the values displayed on the tester while cranking.

      Standard: Values are displayed continuously. 

    NG: REPAIR OR REPLACE CRANKSHAFT POSITION SENSOR CIRCUIT 

    OK: REPLACE ECM 

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