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Fuel Pump Control Circuit [09/2017 - ]: Procedure

  1. PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE FUEL PUMP/SPEED) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Active Test / Control the Fuel Pump/Speed.

      Powertrain > Engine > Active Test 

      Tester Display
      Control the Fuel Pump / Speed
    5. Check whether operating sounds can be heard while operating the fuel pump using the Techstream.

      OK

      Operating sounds can be heard from the fuel pump.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  4

    Result: 

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (ECM - FUEL PUMP CONTROL ECU ASSEMBLY - FUEL SUCTION TUBE WITH PUMP AND GAUGE ASSEMBLY) 
    1. Disconnect the A12 ECM connector.
    2. Disconnect the U40 and U41 fuel pump control ECU assembly connectors.
    3. Disconnect the U8 fuel suction tube with pump and gauge assembly connector.
    4. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A12-17 (FPC) - U41-1 (FPC) Always Below 1 Ω
      U40-1 (FP) - U8-4 (B2) Always Below 1 Ω
      U40-2 (FP-) - U8-5 (E2) Always Below 1 Ω
      A12-17 (FPC) or U41-1 (FPC) - Body ground and other terminals Always 10 kΩ or higher
      U40-1 (FP) or U8-4 (B2) - Body ground and other terminals Always 10 kΩ or higher
      U40-2 (FP-) or U8-5 (E2) - 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  3

  3. REPLACE FUEL PUMP CONTROL ECU ASSEMBLY 
    1. Replace the fuel pump control ECU assembly.

      Refer to REMOVAL [09/2017 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  10

  4. INSPECT FUEL PUMP CONTROL ECU ASSEMBLY (POWER SOURCE VOLTAGE) 
    GTY640935Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to Fuel Pump Control ECU Assembly)
    1. Disconnect the fuel pump control ECU assembly 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 Switch Condition Specified Condition
      U41-4 (+B) - U41-3 (E) Engine switch on (IG) 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  11

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU ASSEMBLY - FUEL SUCTION TUBE WITH PUMP AND GAUGE ASSEMBLY) 
    1. Disconnect the U40 fuel pump control ECU assembly connector.
    2. Disconnect the U8 fuel suction tube with pump and gauge assembly connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      U40-1 (FP) - U8-4 (B2) Always Below 1 Ω
      U40-2 (FP-) - U8-5 (E2) Always Below 1 Ω
      U40-1 (FP) or U8-4 (B2) - Body ground and other terminals Always 10 kΩ or higher
      U40-2 (FP-) or U8-5 (E2) - 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  6

  6. INSPECT FUEL PUMP WITH FILTER ASSEMBLY (FOR LOW PRESSURE SIDE) 
    1. Inspect the fuel pump with filter assembly (for low pressure side).

      Refer to INSPECTION [10/2015 - ]

      HINT: 

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

      Refer to INITIALIZATION [10/2015 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE FUEL PUMP WITH FILTER ASSEMBLY (FOR LOW PRESSURE SIDE). Refer to  REMOVAL [09/2017 - ] 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU ASSEMBLY - BODY GROUND) 
    1. Disconnect the U41 fuel pump control ECU assembly connector.
    2. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      U41-3 (E) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (ECM - FUEL PUMP CONTROL ECU ASSEMBLY) 
    1. Disconnect the A12 ECM connector.
    2. Disconnect the U41 fuel pump control ECU assembly connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A12-17 (FPC) - U41-1 (FPC) Always Below 1 Ω
      A12-14 (DI) - U41-2 (DI) Always Below 1 Ω
      A12-17 (FPC) or U41-1 (FPC) - Body ground and other terminals Always 10 kΩ or higher
      A12-14 (DI) or U41-2 (DI) - 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  9

  9. REPLACE FUEL PUMP CONTROL ECU ASSEMBLY 
    1. Replace the fuel pump control ECU assembly.

      Refer to REMOVAL [09/2017 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  10

  10. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED 
    1. Check the fuel pump operation.

      Refer to PROCEDURE - Step 1

      OK

      Malfunction has been repaired successfully.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE ECM. Refer to  REMOVAL [09/2017 - ] 

  11. CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU ASSEMBLY - BODY GROUND) 
    1. Disconnect the U41 fuel pump control ECU assembly connector.
    2. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      U41-3 (E) - 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. INSPECT C/OPN RELAY 
    1. Inspect the C/OPN relay.

      Refer to PROCEDURE - Step 1

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE RELAY (C/OPN) 

    Result: 

    OK 

    See step  13

  13. CHECK HARNESS AND CONNECTOR (C/OPN RELAY - FUEL PUMP CONTROL ECU ASSEMBLY) 
    1. Remove the C/OPN relay from the No. 3 engine room relay block.
    2. Disconnect the U41 fuel pump control ECU assembly connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      3 (C/OPN relay holder) - U41-4 (+B) Always Below 1 Ω
      3 (C/OPN relay holder) or U41-4 (+B) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  14

  14. CHECK HARNESS AND CONNECTOR (EFI MAIN NO. 2 RELAY - C/OPN RELAY) 
    1. Remove the EFI MAIN NO. 2 relay from the No. 3 engine room relay block.
    2. Remove the C/OPN relay from the No. 3 engine room relay block.
    3. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      3 (EFI MAIN NO. 2 relay holder) - 5 (C/OPN relay holder) Always Below 1 Ω
      3 (EFI MAIN NO. 2 relay holder) - 1 (C/OPN relay holder) Always Below 1 Ω
      3 (EFI MAIN NO. 2 relay holder) or 5 (C/OPN relay holder) - Body ground and other terminals Always 10 kΩ or higher
      3 (EFI MAIN NO. 2 relay holder) or 1 (C/OPN relay holder) - 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  15

  15. INSPECT EFI MAIN NO. 2 RELAY 
    1. Inspect the EFI MAIN NO. 2 relay.

      Refer to PROCEDURE - Step 2

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE EFI MAIN NO. 2 RELAY 

    Result: 

    OK 

    See step  16

  16. CHECK HARNESS AND CONNECTOR (EFI MAIN NO. 2 RELAY - ECM) 
    1. Remove the EFI MAIN NO. 2 relay from the No. 3 engine room relay block.
    2. Disconnect the A12 ECM connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1 (EFI MAIN NO. 2 relay holder) - A12-3 (MREL) Always Below 1 Ω
      1 (EFI MAIN NO. 2 relay holder) or A12-3 (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  17

  17. CHECK HARNESS AND CONNECTOR (EFI MAIN NO. 2 RELAY - BODY GROUND) 
    1. Remove the EFI MAIN NO. 2 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 MAIN NO. 2 relay holder) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - EFI MAIN NO. 2 RELAY) 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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