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Fuel Pump Control Circuit [10/2015 - ]: Procedure

  1. INSPECT FUEL PUMP CONTROL ECU 
    GTY633340Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 Fuel Pump Control ECU - -
    1. Remove the fuel pump control ECU.

      Refer to REMOVAL [10/2015 - ]

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      U65-1 (+B) - U65-3 (GND) Always 200 Ω or higher
      U65-1 (+B) - U65-2 (FPC) Always 2 kΩ or higher
      U65-2 (FPC) - U65-3 (GND) Always 10 kΩ or higher
      U64-1 (FPG) - U65-3 (GND) Always 1 kΩ or higher
      U64-2 (FPU) - U65-3 (GND) Always 2 kΩ or higher
      U64-3 (FPV) - U65-3 (GND) Always 2 kΩ or higher
      U64-4 (FPW) - U65-3 (GND) Always 2 kΩ or higher

      HINT: 

      This procedure checks for an internal short of the fuel pump control ECU when its transistor is stuck on.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE FUEL PUMP CONTROL ECU. Refer to  REMOVAL [10/2015 - ] 

    Result: 

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (POWER SOURCE OF FUEL PUMP CONTROL ECU) 
    GTY656802Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to Fuel Pump Control ECU)
    1. Disconnect the fuel pump control ECU connector.
    2. Turn the engine switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      U65-1 (+B) - U65-3 (GND) Engine switch on (IG) 11 to 14 V

      HINT: 

      Make a note of the measured voltage as it may be used in a following Active Test.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  7

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU - ECM) 
    1. Disconnect the fuel pump control ECU connector.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      U65-2 (FPC) - A78-21 (FPC) Always Below 1 Ω
      U65-2 (FPC) or A78-21 (FPC) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  4

  4. PERFORM ACTIVE TEST USING TECHSTREAM (FUEL PUMP SINGLE PHASE ENERGIZATION) 
    GTY649255Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 Fuel Pump Control ECU - -
    1. Disconnect the fuel pump control ECU connector.
    2. Connect the Techstream to the DLC3.
    3. Turn the engine switch on (IG).
    4. Turn the Techstream on.
    5. Enter the following menus: Powertrain / Engine / Active Test / Fuel Pump Single Phase Energization.
    6. Operate the fuel pump control ECU using the Active Test function and measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Techstream Operation Specified Condition
      U64-2 (FPU) - Body ground U Phase 4.4 to 8.4 V*
      U64-3 (FPV) - Body ground V Phase 4.4 to 8.4 V*
      U64-4 (FPW) - Body ground W Phase 4.4 to 8.4 V*

      HINT: 

      • *: This Active Test restricts the fuel pump control ECU output duty cycle to 50%. Therefore, the output voltage of the fuel pump control ECU will be approximately 50% of the power source voltage measured in a previous step.
      • Before performing this inspection, check that the battery voltage is between 11 and 14 V (not depleted).

      Result

      Result Proceed to
      The U phase, V phase and W phase are all normal A
      The U phase, V phase or W phase is abnormal B
      The U phase, V phase and W phase are all abnormal C

    Result: 

    B 

    REPLACE FUEL PUMP CONTROL ECU. Refer to  REMOVAL [10/2015 - ] 

    Result: 

    C 

    See step  6

    Result: 

    A 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU - FUEL PUMP (FOR LOW PRESSURE SIDE)) 
    1. Disconnect the fuel pump control ECU connector.
    2. Disconnect the fuel pump (for low pressure side) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      U64-2 (FPU) - U61-3 (BLPU) Always Below 1 Ω
      U64-3 (FPV) - U61-4 (BLPV) Always Below 1 Ω
      U64-4 (FPW) - U61-2 (BLPW) Always Below 1 Ω
      U64-2 (FPU) or U61-3 (BLPU) - Body ground and other terminals Always 10 kΩ or higher
      U64-3 (FPV) or U61-4 (BLPV) - Body ground and other terminals Always 10 kΩ or higher
      U64-4 (FPW) or U61-2 (BLPW) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

      HINT: 

      Perform "Inspection After Repair" after replacing the fuel pump (for low pressure side).

      Refer to INITIALIZATION [10/2015 - 09/2018] , or refer to INITIALIZATION [09/2018 - ]

    Result: 

    OK 

    REPLACE FUEL PUMP (FOR LOW PRESSURE SIDE). Refer to  REMOVAL [10/2015 - 09/2016]  , or refer to  REMOVAL [09/2016 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  6. INSPECT ECM (FPC TERMINAL) 
    GTY682257Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to Fuel Pump Control ECU)
    1. Disconnect the fuel pump control ECU connector.
    2. Connect the Techstream to the DLC3.
    3. Turn the engine switch on (IG).
    4. Turn the Techstream on.
    5. Enter the following menus: Powertrain / Engine / Active Test / Fuel Pump Single Phase Energization.
    6. Operate the fuel pump control ECU using the Active Test function and measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Techstream Operation Specified Condition
      U65-2 (FPC) - Body ground Before Active Test → During Active Test Before Active Test: Resistance is stable → During Active Test: Resistance fluctuates*

      HINT: 

      *: Using the Active Test, duty control of the transistors in the ECM will be performed. Due to the duty control, resistance of the FPC terminal will be unstable during the Active Test. If the resistance is stable before the Active Test and fluctuates while performing the Active Test, it can be determined that the transistor is operating. If the transistor does not operate during the Active Test, the ECM may be malfunctioning.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE FUEL PUMP CONTROL ECU. Refer to  REMOVAL [10/2015 - ] 

    Result: 

    NG 

    REPLACE ECM. Refer to  REMOVAL [10/2015 - ] 

  7. CHECK HARNESS AND CONNECTOR (POWER SOURCE VOLTAGE OF EFI MAIN3 RELAY) 
    GTY629694Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 No. 3 Engine Room Relay Block
    *2 EFI MAIN3 Relay
    1. Remove the EFI MAIN3 relay from the No. 3 engine room relay block.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      5 (EFI MAIN3 relay) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. INSPECT EFI MAIN3 RELAY 
    1. Inspect the EFI MAIN3 relay.

      Refer to PROCEDURE - Step 5

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE EFI MAIN3 RELAY 

    Result: 

    OK 

    See step  9

  9. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - ECM) 
    1. Remove the No. 1 integration relay from the No. 2 engine room relay block and junction block assembly.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2E-6 - A78-46 (MREL) Always Below 1 Ω
      2E-6 or A78-46 (MREL) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  10

  10. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - EFI MAIN3 RELAY) 
    1. Remove the EFI MAIN3 relay from the No. 3 engine room relay block.
    2. Remove the No. 1 integration relay from the No. 2 engine room relay block and junction block assembly.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2E-5 - 1 (EFI MAIN3 relay) Always Below 1 Ω
      2E-5 or 1 (EFI MAIN3 relay) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  11

  11. CHECK HARNESS AND CONNECTOR (EFI MAIN3 RELAY - BODY GROUND) 
    1. Remove the EFI MAIN3 relay from the No. 3 engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2 (EFI MAIN3 relay) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  12

  12. CHECK HARNESS AND CONNECTOR (EFI MAIN3 RELAY - FUEL PUMP CONTROL ECU) 
    1. Remove the EFI MAIN3 relay from the No. 3 engine room relay block.
    2. Disconnect the fuel pump control ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      3 (EFI MAIN3 relay) - U65-1 (+B) Always Below 1 Ω
      3 (EFI MAIN3 relay) or U65-1 (+B) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  13

  13. CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU - BODY GROUND) 
    1. Disconnect the fuel pump control ECU connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      U65-3 (GND) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    GO TO ECM POWER SOURCE CIRCUIT. Refer to  ECM Power Source Circuit [10/2015 - ]  

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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