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Inspection Procedure

Hand-held tester: 

  1. Connect hand-held tester, and check operation of fuel pump. 

    PREPARATION: 

    1. Connect the hand-held tester to the DLC3.
    2. Turn the ignition switch ON and push the hand-held tester main switch ON.
    3. Use the ACTIVE TEST mode to operate the fuel pump.
      Fig 1: Checking Operation Of Fuel Pump
      G02835955Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    CHECK: 

    Check that the pulsation damper screw rises up when the fuel pump is operated by the hand-held tester.

    OK: 

    The pulsation damper screw rises up. 

    1. OK: Check for starter signal circuit (See  STARTER SIGNAL CIRCUIT  ). 
    2. OK: Go to next step. 
  2. Check for ECM power source circuit (See  ECM POWER SOURCE CIRCUIT  ). 
    1. NG: Repair or replace. 
    2. OK: Go to next step. 
  3. Check circuit opening relay (Marking: C/OPN) (See  INSPECTION  ).  
    1. NG: Replace circuit opening relay. 
    2. OK: Go to next step. 
  4. Check voltage between terminal FC of ECM connector and body ground. 

    PREPARATION: 

    1. Remove the glove compartment (See COMPONENTS ).
    2. Turn the ignition switch ON.
      Fig 2: Measuring Voltage Terminal FC ECM Connector & Body Ground
      G02835956Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    CHECK: 

    Measure the voltage between terminal FC of the ECM connector and body ground.

    OK: 

    Voltage: 9 - 14 V 

    1. OK: Go to step 5. 
    2. NG: Check for open in harness and connector between EFI main relay (Marking: EFI) and circuit opening relay (Marking: C/OPN), and circuit opening relay and ECM (See  PROCEDURE  ). 
  5. Check fuel pump (See  FUEL PUMP  ). 
    1. NG: Repair or replace fuel pump. 
    2. OK: Go to next step. 
  6. Check for open in harness and connector between circuit opening relay (Marking: C/OPN) and fuel pump, and fuel pump and body ground (See  PROCEDURE  ). 
    1. NG: Repair or replace harness or connector. 
    2. OK: Check and replace ECM (See  PROCEDURE  ). 

OBD II scan tool (excluding hand-held tester): 

  1. Check operation of fuel pump. 

    PREPARATION: 

    1. Remove the glove compartment (See ENGINE CONTROL MODULE (ECM) ).
    2. Turn the ignition switch ON.

    CHECK: 

    1. Connect between terminal FC of the ECM connector and body ground.
    2. Check that the pulsation damper screw rises up when connecting between terminal FC of the ECM connector and body ground.
      Fig 3: Checking Operation Of Fuel Pump
      G02835957Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: 

    The pulsation damper screw rises up. 

    1. OK: Check for starter signal circuit (See  STARTER SIGNAL CIRCUIT  ). 
    2. NG: Go to next step. 
  2. Check for ECM power source circuit (See  ECM POWER SOURCE CIRCUIT  ). 
    1. NG: Repair or replace. 
    2. OK: Go to next step. 
  3. Check circuit opening relay (Marking: C/OPN) (See  INSPECTION  ). 
    1. NG: Replace circuit opening relay. 
    2. OK: Go to next step. 
  4. Check voltage between terminal FC of ECM connector and body ground. 

    PREPARATION: 

    1. Remove the glove compartment (See COMPONENTS ).
    2. Turn the ignition switch ON.
      Fig 4: Measuring Voltage Terminal FC Of ECM Connector & Body Ground
      G02835958Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    CHECK: 

    Measure the voltage between terminal FC of the ECM connector and body ground.

    OK: 

    Voltage: 9 - 14 V 

    1. OK: Go to step 5. 
    2. NG: Check for open in harness and connector between EFI main relay (Marking: EFI) and circuit opening relay (Marking: C/OPN), and circuit opening relay and ECM (See  PROCEDURE  ).  
  5. Check fuel pump (See  FUEL PUMP  ).  
    1. NG: Repair or replace fuel pump. 
    2. OK: Go to next step. 
  6. Check for open in harness and connector between circuit opening relay (Marking: C/OPN) and fuel pump, and fuel pump and body ground (See  PROCEDURE  ).  
    1. NG: Repair or replace harness or connector. 
    2. OK: Check and replace ECM (See  PROCEDURE  ).