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Fuel Pump Control Circuit: Wiring Diagram

Refer to DTC P0230 .

  1. CHECK FUEL PUMP OPERATION 
    1. Check if there is pressure in the fuel inlet hose.

      HINT:

      If there is fuel pressure, you will hear the sound of fuel flowing.

    OK : Go to step   12 

    NG : GO TO NEXT STEP 

  2. PERFORM ACTIVE TEST BY INTELLIGENT TESTER (OPERATE CIRCUIT OPENING RELAY) 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the engine switch on (IG) and turn the intelligent tester ON.
    3. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / FUEL PUMP / SPD.
    4. Check the operation of the relay while operating it using the intelligent tester.

      OK: 

      Operating noise can be heard from the relay. 

    OK : Go to step   8 

    NG : GO TO NEXT STEP 

  3. INSPECT ECM POWER SOURCE CIRCUIT 

    NG : REPAIR OR REPLACE POWER SOURCE CIRCUIT COMPONENTS 

    OK : GO TO NEXT STEP 

  4. INSPECT FUSE (F/PMP FUSE) 
    1. Remove the F/PMP fuse from the engine room No. 2 relay block, junction block.
    2. Measure the resistance of the F/PMP fuse.

      Standard resistance: 

      Below 1 Ω 

    NG : CHECK FOR SHORT IN ALL HARNESS AND COMPONENTS CONNECTED TO FUSE 

    Fig 1: Identifying F/PMP Fuse
    G04018001Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : GO TO NEXT STEP 

  5. INSPECT INTEGRATION RELAY (EFI NO.2 RELAY) 
    1. Remove the integration relay from the engine room No. 2 junction block.
    2. Measure the resistance of the EFI NO. 2 relay.

      Standard resistance 

      INTEGRATION RELAY TERMINALS RESISTANCE SPECIFICATIONS

      Tester Connection Specified Condition
      2B-4 - 2C-1  10 kΩ or higher 
      2B-4 - 2C-1  Below 1 Ω (when battery voltage applied to terminals 2B-3 and 2B-2) 

    NG : REPLACE INTEGRATION RELAY 

    Fig 2: Identifying Integration Relay
    G04018002Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : GO TO NEXT STEP 

  6. INSPECT INTEGRATION RELAY (C/OPN RELAY) 
    1. Remove the integration relay from the engine room No. 2 junction block.
    2. Measure the resistance of the C/OPN relay.

      Standard resistance 

      INTEGRATION RELAY TERMINALS RESISTANCE SPECIFICATIONS

      Tester Connection Specified Condition
      2B-6 - 2B-8  10 kΩ or higher 
      2B-6 - 2B-8  Below 1 Ω (when battery voltage applied to terminals 2B-6 and 2B-7) 

    NG : REPLACE INTEGRATION RELAY 

    Fig 3: Identifying Integration Relay
    G04018003Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : GO TO NEXT STEP 

  7. INSPECT ECM (FC VOLTAGE) 
    1. Turn the engine switch on (IG).
    2. Measure the voltage of the A6 and E7 ECM connectors.

      Standard voltage 

      ECM TERMINALS VOLTAGE SPECIFICATIONS

      Tester Connection Specified Condition
      FC (A6-14) - E1 (E7-7)  9 to 14 V 

    OK : REPLACE ECM 

    Fig 4: Identifying A6 And E7 ECM Connectors
    G04018004Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG : CHECK AND REPAIR HARNESS AND CONNECTOR (ECM - CIRCUIT OPENING RELAY) 

  8. INSPECT F/PMP RELAY 
    1. Remove the F/PMP relay from the engine room No. 2 relay block.
    2. Measure the resistance of the F/PMP relay.

      Standard resistance 

      F/PMP RELAY TERMINALS RESISTANCE SPECIFICATIONS

      Tester Connection Specified Condition
      3 - 4  10 kΩ or higher 
      3 - 4  Below 1 Ω (when battery voltage applied to terminals 1 and 2) 

    NG : REPLACE F/PMP RELAY 

    Fig 5: Identifying Relay Test Terminals
    G04054635Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : GO TO NEXT STEP 

  9. INSPECT FUEL PUMP 
    1. Inspect fuel pump resistance.
      1. Measure the resistance between terminals 4 and 5.

        Standard resistance: 

        0.2 to 3.0 Ω at 20°C (68°F) 

    2. Inspect fuel pump operation.
      1. Apply 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 fuel pump as far away from the battery as possible.
        • Always switch at the battery side.

    NG : REPLACE FUEL PUMP 

    Fig 6: Identifying Fuel Pump Connectors
    G04018006Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : GO TO NEXT STEP 

  10. CHECK HARNESS AND CONNECTOR (FUEL PUMP - F/PMP RELAY) 
    1. Check the harness and the connectors between the fuel pump and the F/PMP relay.
      1. Disconnect the fuel pump connector.
      2. Remove the F/PMP relay from the engine room No. 2 relay block.
      3. Measure the resistance of the wire harness side connectors.

        Standard resistance (Check for open) 

        FUEL PUMP CONNECTOR TERMINALS RESISTANCE SPECIFICATIONS (CHECK FOR OPEN)

        Tester Connection Specified Condition
        Fuel pump (V11-4) - F/PMP relay (4)  Below 1 Ω 

        Standard resistance (Check for short) 

        FUEL PUMP CONNECTOR TERMINALS RESISTANCE SPECIFICATIONS (CHECK FOR SHORT)

        Tester Connection Specified Condition
        Fuel pump (V11-4) or F/PMP (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 fuel pump connector.
      2. Measure the resistance of the wire harness side connector and the body ground.

        Standard resistance (Check for open) 

        FUEL PUMP CONNECTOR TERMINALS RESISTANCE SPECIFICATIONS (CHECK FOR OPEN)

        Tester Connection Specified Condition
        Fuel pump (V11-5) - Body ground  10 kΩ or higher 

    NG : REPAIR OR REPLACE HARNESS AND CONNECTOR 

    Fig 7: Identifying Fuel Pump And F/PMP Relay Connectors
    G04018007Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : GO TO NEXT STEP 

  11. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - F/PMP RELAY) 
    1. Remove the integration relay from the engine room No. 2 junction block.
    2. Remove the F/PMP relay from the engine room No. 2 junction block.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance (Check for open) 

      INTEGRATION RELAY TERMINALS RESISTANCE SPECIFICATIONS (CHECK FOR OPEN)

      Tester Connection Specified Condition
      Integration relay (2B-8) - F/PMP relay (1)  Below 1 Ω 
      Below 1 Ω 
      Integration relay (2B-8) - F/PMP relay (3)   

      Standard resistance (Check for short) 

      INTEGRATION RELAY TERMINALS RESISTANCE SPECIFICATIONS (CHECK FOR SHORT)

      Tester Connection Specified Condition
      Circuit opening relay (2B-8) or F/PMP relay (1) - Body ground  10 kΩ or higher 
      Circuit opening relay (2B-8) or F/PMP relay (3) - Body ground  10 kΩ or higher 

    NG : REPAIR OR REPLACE HARNESS AND CONNECTOR 

    Fig 8: Identifying F/PMP Relay Connectors
    G04018008Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : REPAIR OR REPLACE INTEGRATION RELAY 

  12. INSPECT F/PMP RELAY 
    1. Remove the F/PMP relay from the engine room No. 2 relay block.
    2. Measure the resistance of the F/PMP relay.

      Standard resistance 

      F/PMP RELAY TERMINALS RESISTANCE SPECIFICATIONS

      Tester Connection Specified Condition
      3 - 4  10 kΩ or higher 
      3 - 4  Below 1 Ω (when battery voltage applied to terminals 1 and 2) 

    NG : REPLACE F/PMP RELAY 

    Fig 9: Identifying Relay Test Terminals
    G04054635Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : GO TO NEXT STEP 

  13. INSPECT FUEL PUMP RESISTER 
    1. Measure the resistance of the fuel pump resistor.

      Standard resistance: 

      0.30 to 0.34 Ω at 20°C (68°F) 

    NG : REPLACE FUEL PUMP RESISTER 

    Fig 10: Measuring Resistance Of Fuel Pump Resistor
    G04018010Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : GO TO NEXT STEP 

  14. CHECK HARNESS AND CONNECTOR (F/PMP RELAY - FUEL PUMP RESISTER) 
    1. Check the harness and the connectors between the F/PMP relay and the fuel pump resistor.
      1. Remove the F/PMP relay from the engine room No. 2 relay block.
      2. Disconnect the fuel pump resistor connector.
      3. Measure the resistance of the wire harness side connectors.

        Standard resistance (Check for open) 

        FUEL PUMP RESISTOR TERMINALS RESISTANCE SPECIFICATIONS (CHECK FOR OPEN)

        Tester Connection Specified Condition
        F/PMP relay (4) - Fuel pump resistor (A45-2)  Below 1 Ω 
        F/PMP relay (3) - Fuel pump resistor (A45-1)  Below 1 Ω 

        Standard resistance (Check for short) 

        FUEL PUMP RESISTOR TERMINALS RESISTANCE SPECIFICATIONS (CHECK FOR SHORT)

        Tester Connection Specified Condition
        Fuel pump relay (4) or Fuel pump resistor (A45-2) - Body ground  10 kΩ or higher 
        Fuel pump relay (4) or Fuel pump resistor (A45-1) - Body ground  10 kΩ or higher 

    OK : PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON  PROBLEM SYMPTOMS TABLE 

    Fig 11: Identifying F/PMP Relay And Fuel Pump Resistor Connectors
    G04018011Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG : REPAIR OR REPLACE HARNESS AND CONNECTOR 

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