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Fuel Pump Control Circuit: Wiring Diagram

Refer to DTC P0230 .

  1. CHECK FUEL PUMP (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 

    OK : Go To Next Step 

  4. INSPECT FUSE (F/PMP FUSE) 
    1. Remove the F/PMP fuse from the engine room J/B and R/B No. 2.
    2. Measure the resistance of the F/PMP fuse.

    Standard resistance: 

    Below 1 Ω 

    NG : REPLACE FUSE 

    Fig 1: Identifying F/PMP Fuse Location
    G04043843Courtesy 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 J/B and R/B No. 2.
    2. Measure the resistance according to the value(s) in the table below.

    Standard resistance 

    STANDARD RESISTANCE

    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
    G04043844Courtesy 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 J/B and R/B No. 2.
    2. Measure the resistance according to the value(s) in the table below.

    Standard resistance 

    STANDARD RESISTANCE

    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
    G04043845Courtesy 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 according to the value(s) in the table below.

    Standard voltage 

    Fig 4: Identifying E4 And A5 ECM Connector
    G04043846Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    STANDARD VOLTAGE

    Tester Connection Specified Condition
    FC (A5-14) - E1 (E4-7) 9 to 14 V

    OK : REPLACE ECM 

    NG : Go To Next Step 

    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 J/B and R/B No. 2.
    2. Measure the resistance according to the value(s) in the table below.

    Standard resistance 

    STANDARD RESISTANCE

    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 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 switch at the battery side.
    Fig 6: Identifying Fuel Pump Connector Terminals
    G04043848Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG : REPLACE FUEL PUMP 

    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 J/B and R/B No. 2.
      3. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open) 

      STANDARD RESISTANCE (CHECK FOR OPEN)

      Tester Connection Specified Condition
      Fuel pump (Q14-4) - F/PMP relay (4) Below 1 Ω
      Fig 7: Identifying F/PMP Relay Location
      G04043849Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance (Check for short) 

      STANDARD RESISTANCE (CHECK FOR SHORT)

      Tester Connection Specified Condition
      Fuel pump (Q14-4) or F/PMP (4) - Body ground 10 kΩ or higher
    2. Check the harness and the connectors between the fuel pump and 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) 

      STANDARD RESISTANCE (CHECK FOR OPEN)

      Tester Connection Specified Condition
      Fuel pump (Q14-5) - Body ground 10 kΩ or higher

      NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

      OK : Go To Next Step 

  11. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - F/PMP RELAY) 
    1. Remove the integration relay from the engine room J/B and R/B No. 2.
    2. Remove the F/PMP relay from the engine room J/B and R/B No. 2.
    3. Measure the resistance according to the value(s) in the table below.

    Standard resistance (Check for open) 

    Fig 8: Identifying F/PMP Relay Location
    G04043850Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    STANDARD RESISTANCE (CHECK FOR OPEN)

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

    Standard resistance (Check for short) 

    STANDARD RESISTANCE (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 OR CONNECTOR 

    OK : REPAIR OR REPLACE INTEGRATION RELAY 

  12. INSPECT F/PMP RELAY 
    1. Remove the F/PMP relay from the engine room J/B and R/B No. 2.
    2. Measure the resistance according to the value(s) in the table below.

    Standard resistance 

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

    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 

    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
    G04043852Courtesy 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 J/B and R/B No. 2.
      2. Disconnect the fuel pump resistor connector.
      3. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open) 

      STANDARD RESISTANCE (CHECK FOR OPEN)

      Tester Connection Specified Condition
      F/PMP relay (4) - Fuel pump resistor (A40-2) Below 1 Ω
      F/PMP relay (3) - Fuel pump resistor (A40-1) Below 1 Ω

      Standard resistance (Check for short) 

      Fig 11: Identifying F/PMP Relay Location
      G04043853Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      STANDARD RESISTANCE (CHECK FOR SHORT)

      Tester Connection Specified Condition
      Fuel pump relay (4) or Fuel pump resistor (A40-2) - Body ground 10 kΩ or higher
      Fuel pump relay (3) or Fuel pump resistor (A40-1) - Body ground 10 kΩ or higher

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

      NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

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