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Home >> Toyota >> 2008 >> Sequoia Platinum, RWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (3UR-FE) - Circuit Testing, Component On-Vehicle Inspection, Removal, Inspection & Installation >> Fuel Pump Control Circuit >> Inspection Procedure

Inspection Procedure

This troubleshooting procedure is based on the premise that the engine is started. If the engine is not started, proceed to the Problem Symptoms Table (See PROBLEM SYMPTOMS TABLE ).

  1. PERFORM ACTIVE TEST USING TECHSTREAM (FUEL PUMP) 
    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 operating sounds can be heard while operating the relay using the Techstream.

      OK: Operating sounds can be heard from relay. 

    NG:  Go to step  4

    OK: Go to Next Step. 

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

      Standard Resistance 

      STANDARD RESISTANCE

      Tester Connection Condition Specified Condition
      O35-1 (FPC) - A27-52 (FPC) Always Below 1 Ω
      O35-2(DI) - A27-18(DI) Always Below 1 Ω
      O35-3 (E) - Body ground Always Below 1 Ω
      O35-1 (FPC) or A27-52 (FPC) - Body ground Always 10 kΩ or more
      O35-2(DI) or A27-18(DI) - Body ground Always 10 kΩ or more

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 1: Identifying ECM And Fuel Pump ECU Connector Terminals
    G05644685Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step. 

  3. INSPECT FUEL PUMP ECU (FPC SIGNAL) 
    1. Disconnect the fuel pump ECU connector.
    2. Crank the engine.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

      STANDARD VOLTAGE

      Tester Connection Condition Specified Condition
      O35-1 (FPC) - 035-3 (E) Engine cranking 2.8 V or higher

    NG: REPLACE ECM  (See REMOVAL  )

    Fig 2: Identifying Fuel Pump ECU Connector Terminals
    G05644686Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE FUEL PUMP ECU  (See REMOVAL )

  4. INSPECT CIRCUIT OPENING RELAY (C/OPN) 
    1. Remove the circuit opening relay (C/OPN) from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      STANDARD RESISTANCE

      Tester Connection Condition Specified Condition
      3-5 When no battery voltage applied to terminals 1 and 2 10 kΩ or higher
      3-5 When battery voltage applied to terminals 1 and 2 Below 1 Ω

    NG: REPLACE CIRCUIT OPENING RELAY (C/OPN) 

    Fig 3: Identifying Circuit Opening Relay Terminals (C/OPN)
    G05644687Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step. 

  5. INSPECT CIRCUIT OPENING RELAY (POWER SOURCE VOLTAGE) 
    1. Remove the circuit opening relay (C/OPN) from the engine room relay block.
    2. Turn the ignition switch to ON.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

      STANDARD VOLTAGE

      Tester Connection Switch Condition Specified Condition
      C/OPN relay (2) - Body ground Ignition switch ON 11 to 14 V
      C/OPN relay (5) - Body ground Ignition switch ON 11 to 14 V

    NG:  Go to step  11

    Fig 4: Identifying Circuit Opening Relay Terminals (C/OPN)
    G05644688Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step. 

  6. CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY - ECM AND FUEL PUMP ECU) 
    1. Remove the circuit opening relay (C/OPN) from the engine room relay block.
    2. Disconnect the ECM connector.
    3. Disconnect the fuel pump ECU connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      STANDARD RESISTANCE

      Tester Connection Condition Specified Condition
      C/OPN relay (1) - A27-48 (FC) Always Below 1 Ω
      C/OPN relay (3) - 035-4 (+B) Always Below 1 Ω
      C/OPN relay (1) or A27-48 (FC) - Body ground Always 10 kΩ or higher
      C/OPN relay (3) or 035-4 (+B) - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 5: Identifying ECM And Circuit Opening Relay Terminals (C/OPN)
    G05644689Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step. 

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

      Standard Resistance 

      STANDARD RESISTANCE

      Tester Connection Condition Specified Condition
      Q1-4(B2)- O36-1 (FP) Always Below 1 Ω
      Q1-5(E2)- O36-2(FP-) Always Below 1 Ω
      Q1-4(B2) or O36-1(FP) - Body ground Always 10 kΩ or higher
      Q1-5(E2) or O36-2 (FP-) - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 6: Identifying Fuel Pump And Fuel Pump ECU Connector Terminals
    G05644690Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step. 

  8. INSPECT FUEL PUMP 
    1. Inspect the fuel pump (See INSPECTION ).

    NG: REPLACE FUEL PUMP  (See REMOVAL )

    OK: Go to Next Step. 

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

      Standard Resistance 

      STANDARD RESISTANCE

      Tester Connection Condition Specified Condition
      O35-1 (FPC) - A27-52 (FPC) Always Below 1 Ω
      O35-2(DI) - A27-18(DI) Always Below 1 Ω
      O35-3 (E) - Body ground Always Below 1 Ω
      O35-1 (FPC) or A27-52 (FPC) - Body ground Always 10 kΩ or more
      O35-2(DI) or A27-18(DI) - Body ground Always 10 kΩ or more

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 7: Identifying ECM And Fuel Pump ECU Connector Terminals
    G05644691Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step. 

  10. INSPECT FUEL PUMP ECU (FPC SIGNAL) 
    1. Disconnect the fuel pump ECU connector.
    2. Crank the engine.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

      STANDARD VOLTAGE

      Tester Connection Condition Specified Condition
      O35-1 (FPC) - 035-3 (E) Engine cranking 2.8 V or higher

    NG: REPLACE ECM  (See REMOVAL  )

    Fig 8: Identifying Fuel Pump ECU Connector Terminals
    G05644692Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE FUEL PUMP ECU  (See REMOVAL )

  11. CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY - FUEL PUMP RELAY AND IGN FUSE) 
    1. Remove the circuit opening relay (C/OPN) from the engine room relay block.
    2. Remove the fuel pump relay (F/PMP) from the engine room relay block.
    3. Remove the IGN fuse from the engine room relay block.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      STANDARD RESISTANCE

      Tester Connection Condition Specified Condition
      C/OPN relay (2) - IGN fuse (2) Always Below 1 Ω
      C/OPN relay (5) - F/PMP relay (3) Always Below 1 Ω
      C/OPN relay (2) or IGN fuse (2) - Body ground Always 10 kΩ or more
      C/OPN relay (5) or F/PMP relay (3) - Body ground Always 10 kΩ or more

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 9: Identifying Fuel Pump Relay Terminals (F/PMP)
    G05644693Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step. 

  12. INSPECT FUEL PUMP RELAY (F/PMP) 
    1. Remove the fuel pump relay (F/PMP) from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      STANDARD RESISTANCE

      Tester Connection Condition Specified Condition
      3-5 When no battery voltage applied to terminals 1 and 2 10 kΩ or higher
      3-5 When battery voltage applied to terminals 1 and 2 Below 1 Ω
      Fig 10: Identifying Fuel Pump Relay Terminals (F/PMP)
      G05644694Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FUEL PUMP RELAY (F/PMP) 

    OK: Go to Next Step. 

  13. CHECK HARNESS AND CONNECTOR (FUEL PUMP RELAY - INTEGRATION RELAY, BATTERY AND BODY GROUND) 
    1. Remove the IGN fuse from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      STANDARD RESISTANCE

      Tester Connection Condition Specified Condition
      IGN fuse Always Below 1 Ω
    3. Reinstall the IGN fuse.
    4. Remove the fuel pump relay (F/PMP) from the engine room relay block.
    5. Remove the integration relay from the engine room relay block.
    6. Disconnect the 1B integration relay connector.
    7. Disconnect the cable from the battery positive (+) terminal.
    8. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      STANDARD RESISTANCE

      Tester Connection Condition Specified Condition
      F/PMP relay (1)-1B-4 Always Below 1 Ω
      F/PMP relay (5) - Positive (+) battery cable Always Below 1 Ω
      F/PMP relay (2) - Body ground Always Below 1 Ω
      F/PMP relay (1) or 1B-4-Body ground Always 10 kΩ or higher
      F/PMP relay (5) or Positive (+) battery cable - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 11: Identifying 1B Integration Relay Connector Terminals
    G05644695Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: GO TO ECM POWER SOURCE CIRCUIT  (See ECM POWER SOURCE CIRCUIT  )

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