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Fuel Pump Control Circuit: Procedure

  1. PERFORM ACTIVE TEST USING TECHSTREAM (FUEL PUMP/SPD) 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Fuel Pump/Speed.
    5. Check whether the fuel pump operating sound occurs when performing the Active Test on the tester.

      Result

      Result Refer to
      Fuel pump operating sound does not occur A
      Fuel pump operating sound occurs B

    B → Refer to step   8 

    A: Refer 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.
      Fig 1: Identifying Main Body ECU Connector Terminals
      GTY161507Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      4B-11 (Main body ECU) - Body ground Ignition switch off Below 1 V
      4F-4 (Main body ECU) - Body ground
      4B-11 (Main body ECU) - Body ground Ignition switch ON 11 to 14 V
      4F-4 (Main body ECU) - Body ground

      Result

      Result Refer to
      Outside standard range A
      Within standard range B

    B → Refer to step   4 

    A: Refer to next step 

  3. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - INTEGRATION RELAY) 
    1. Remove the integration relay from the engine room relay block.
      Fig 2: Identifying Main Body ECU And Integration Relay Connector Terminals
      GTY161535Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the main body ECU connectors.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      1B-4 (Integration relay) - 4F-4 (Main body ECU) Always Below 1 Ω
      1A-4 (Integration relay) - 4B-11 (Main body ECU) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      4F-4 (Main body ECU) - Body ground Always 10 kΩ or higher
      4B-11 (Main body ECU) - Body ground Always 10 kΩ or higher
    4. Reinstall the integration relay.
    5. Reconnect the main body ECU connectors.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → Refer to step   10 

  4. INSPECT MAIN BODY ECU (C/OPN RELAY) 
    1. Remove the main body ECU.
      Fig 3: Identifying Main Body ECU Connector Terminals
      GTY162292Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      4A-8 - 4B-11 Battery voltage not applied 10 kΩ or higher
      Battery voltage applied to terminals 4D-1 and 4E-5 Below 1 Ω
    3. Reinstall the main body ECU.

    NG → Refer to step   11 

    OK: Refer to next step 

  5. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - ECM) 
    1. Disconnect the ECM connector.
      Fig 4: Identifying Main Body ECU And ECM Connector
      GTY164050Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the main body ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      4E-5 (Main body ECU) - A21-7 (FC) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      4E-5 (Main body ECU) or A21-7 (FC) - Body ground Always 10 kΩ or higher
    4. Reconnect the main body ECU connector.
    5. Reconnect the ECM connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Refer to next step 

  6. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - FUEL PUMP - BODY GROUND) 
    1. Check the harness and the connectors between the main body ECU (C/OPN relay) and the fuel pump.
      Fig 5: Identifying Fuel Pump Connector Terminals
      GTY164820Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Disconnect the main body ECU connector.
      2. Disconnect the fuel pump connector.
      3. Measure the resistance according to the value(s) in the table below.

        Standard Resistance (Check for Open)

        Tester Connection Condition Specified Condition
        4A-8 (Main body ECU) - L7-4 (Fuel pump) Always Below 1 Ω

        Standard Resistance (Check for Short)

        Tester Connection Condition Specified Condition
        4A-8 (Main body ECU) or L7-4 (Fuel pump) - Body ground Always 10 kΩ or higher
      4. Reconnect the main body ECU connector.
      5. Reconnect the fuel pump connector.
    2. Check the harness and the connectors between the fuel pump and the body ground.
      1. Disconnect the fuel pump connector.
      2. Measure the resistance according to the value(s) in the table below.

        Standard Resistance (Check for Open)

        Tester Connection Condition Specified Condition
        L7-5 (Fuel pump) - Body ground Always Below 1 Ω
    3. Reconnect the fuel pump connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Refer to next step 

  7. INSPECT FUEL PUMP 
    1. Remove the fuel pump.
    2. Inspect fuel pump resistance.
      Fig 6: Identifying Fuel Pump Connector Terminals
      GTY164383Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Measure the resistance according to the value(s) in the table below.

        Standard Resistance

        Tester Connection Condition Specified Condition
        4 (+) - 5 (-) 20°C (68°F) 0.2 to 3.0 Ω
    3. 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.
        • Always turn the voltage on and off on the battery side, not the fuel pump side.

        OK

        The fuel pump operates normally.

    4. Reinstall the fuel pump.

    NG → Refer to step   12 

    OK → Refer to step   13 

  8. READ VALUE USING TECHSTREAM (STARTER SIG) 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Starter Signal.
    5. Check the result when the ignition switch is turned to ON and START.

      OK

      Ignition Switch Position Starter Signal
      ON Close
      START Open

    NG → Refer to step   14 

    OK: Refer to next step 

  9. READ VALUE USING TECHSTREAM (ENGINE SPD) 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Engine Speed.
    5. Read the values displayed on the tester while cranking.

      OK

      Values are displayed continuously.

    NG → Refer to step   15 

    OK → Refer to step   16 

  10. Refer to ECM POWER SOURCE CIRCUIT. Refer to  ECM Power Source Circuit  
  11. REPLACE MAIN BODY ECU. Refer to  REMOVAL - Step 71 
  12. REPLACE FUEL PUMP. Refer to  REMOVAL 
  13. REPLACE ECM. Refer to  REMOVAL 
  14. REPAIR OR REPLACE STARTING SYSTEM. Refer to  INSPECTION PROCEDURE 
  15. REPAIR OR REPLACE CRANKSHAFT POSITION SENSOR CIRCUIT. Refer to  INSPECTION PROCEDURE 
  16. REPLACE ECM. Refer to  REMOVAL 
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