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Home >> Toyota >> 2006 >> Tacoma Base, 2D Pickup, 4WD >> Repair and Diagnosis >> Engine Performance >> Engine Control System (2TR-FE) >> SFI System >> Fuel Pump Control Circuit >> Inspection Procedure
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Inspection Procedure

  1. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (OPERATION OF CIRCUIT OPENING RELAY) 
    1. Connect an intelligent tester to the DLC3.
    2. Turn the ignition switch to ON and turn the tester ON.
    3. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / FUEL PUMP/ SPD.
    4. Check whether relay operating sounds can be heard while operating the relay using the tester.

      OK: Relay operating sounds can be heard from relay. 

    OK: Go to step   7 

    NG: Go to next step 

  2. INSPECT ECM POWER SOURCE CIRCUIT 

    NG: REPAIR OR REPLACE POWER SOURCE CIRCUIT 

    OK: Go to next step 

  3. INSPECT CIRCUIT OPENING RELAY (C/OPN RELAY) 
    1. Remove the circuit opening (C/OPN) relay from the engine room R/B.
    2. Check the circuit opening relay resistance.

      Standard Resistance 

      TESTER CONNECTIONS AND SPECIFIED CONDITION TABLE

      Tester Connections Specified Conditions
      3 - 5 10 kΩ or higher
      3 - 5 Below 1 Ω
      (when battery voltage applied to terminals 1 and 2)
    3. Reinstall the circuit opening relay.
      Fig 1: Checking Circuit Opening Relay Resistance
      G04407868Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE CIRCUIT OPENING RELAY 

    OK: Go to next step 

  4. INSPECT ECM (FC VOLTAGE) 
    1. Turn the ignition switch to ON.
    2. Measure the voltage between the terminals of the ECM connectors.

      Standard Voltage 

      TESTER CONNECTIONS AND SPECIFIED CONDITION TABLE

      Tester Connections Specified Conditions
      FC (E8-25) - E1 (E4-3) 9 to 14 V

    OK: REPLACE ECM 

    Fig 2: Identifying E4 & E8 ECM Connector Terminals
    G04407869Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (IGNITION SWITCH - CIRCUIT OPENING RELAY) 
    1. Disconnect the I7 ignition switch connector.
    2. Remove the circuit opening (C/OPN) relay from the engine room R/B.
    3. Check the resistance.

      Standard Resistance (Check for open) 

      TESTER CONNECTIONS AND SPECIFIED CONDITION TABLE

      Terminal Connections Specified Conditions
      IG2 (I7-6) - Engine room R/B (Circuit opening relay terminal 1) Below 1 Ω

      Standard Resistance (Check for short) 

      TESTER CONNECTIONS AND SPECIFIED CONDITION TABLE

      Terminal Connections Specified Conditions
      IG2 (I7-6) or Engine room R/B (Circuit opening relay terminal 1) - Body ground 10 kΩ or higher
    4. Reinstall the circuit opening relay.
    5. Reconnect the ignition switch connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 3: Removing Circuit Opening (C/OPN) Relay From Engine Room R/B
    G04407870Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  6. CHECK HARNESS AND CONNECTOR (ECM - CIRCUIT OPENING RELAY) 
    1. Disconnect the E8 ECM connector.
    2. Remove the circuit opening (C/OPN) relay from the engine room R/B.
    3. Check the resistance.

      Standard Resistance (Check for open) 

      TESTER CONNECTIONS AND SPECIFIED CONDITION TABLE

      Tester Connections Specified Conditions
      FC (E8-25) - Engine room R/B (Circuit opening relay terminal 2) Below 1 Ω

      Standard Resistance (Check for short) 

      TESTER CONNECTIONS AND SPECIFIED CONDITION TABLE

      Tester Connections Specified Conditions
      FC (E8-25) or Engine room R/B (Circuit opening relay terminal 2) - Body ground 10 kΩ or higher
    4. Reinstall the circuit opening relay.
    5. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 4: Disconnecting E8 ECM Connector
    G04407871Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE ECM 

  7. INSPECT FUEL PUMP ASSEMBLY 

    HINT:

    Refer to Fuel Pump Inspection (See INSPECTION ).

    NG: REPLACE FUEL PUMP ASSEMBLY 

    OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY - FUEL PUMP, FUEL PUMP - BODY GROUND) 
    1. Remove the circuit opening (C/OPN) relay from the engine room R/B.
    2. Disconnect the F19 fuel pump connector.
    3. Check the resistance.

      Standard Resistance (Check for open) 

      TESTER CONNECTIONS AND SPECIFIED CONDITION TABLE

      Tester Connections Specified Conditions
      Engine room R/B (Circuit opening relay terminal 3) - Fuel pump (F19-4) Below 1 Ω
      Fuel pump (F19-5) - Body ground Below 1 Ω

      Standard Resistance (Check for short) 

      TESTER CONNECTIONS AND SPECIFIED CONDITION TABLE

      Tester Connections Specified Conditions
      Engine room R/B (Circuit opening relay terminal 3) or Fuel pump (F19-4) - Body ground 10 kΩ or higher
    4. Reconnect the fuel pump connector.
    5. Reinstall the circuit opening relay.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 5: Removing Circuit Opening (C/OPN) Relay From Engine Room R/B
    G04407872Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: CHECK AND REPLACE HARNESS AND CONNECTOR (EFI RELAY - C/OPN RELAY) 

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